Research: terminal color schemes for DropTerm’s Appearance settings

Date: 2026-10-02 Question: How should DropTerm represent, ship, and apply user-selectable terminal color schemes (16 ANSI colors, fg/bg, cursor, bright/dim variants), and how should they interact with the system light/dark preference?

TL;DR

Copy cosmic-term’s model — it is the same stack solving the same problem. cosmic-term (pop-os/cosmic-term, master 3ef31d7, 2026-10-01) represents a scheme as a serde struct ColorScheme (name, foreground, background, cursor, bright_foreground, dim_foreground, plus normal/bright/dim tables of 8 named colors each, all Option<HexColor>) defined in src/config.rs. User schemes live inside the cosmic-config config file as BTreeMap<ColorSchemeId, ColorScheme> — one map per dark/light kind — and the selected scheme per mode is a plain String name (syntax_theme_dark / syntax_theme_light). Schemes are applied by converting to alacritty_terminal::term::color::Colors (a [Option<Rgb>; 269]) and copying slots into each terminal on config change. DropTerm already vendors the last two steps (src/terminal/theme_source.rs, engine.rs::set_config), so the work is: a real ColorScheme type, a named scheme registry (built-ins compiled in — cosmic-term’s repo ships 30 importable RON files under color-schemes/), and a picker in the Appearance settings section instead of the raw color_scheme_dark/color_scheme_light strings currently buried in Advanced. Light/dark auto-switching already works end-to-end in DropTerm via libcosmic’s system_theme_update hooks — nothing new is needed there for a scheme list.

Note: util-linux terminal-colors.d(5) does not apply — it configures color output of CLI utilities (dmesg, ls, …), not terminal-emulator palettes. There is no freedesktop standard for emulator schemes; every emulator rolls its own format. The industry-consensus field set for a minimal-but-complete scheme is: name/metadata, foreground, background, 16 ANSI colors, cursor (+ optional cursor text), optional selection fg/bg, optional bright/dim variants (derivable).

What DropTerm does today

• Two hardcoded schemes — theme_source::cosmic_dark() / cosmic_light(), vendored from cosmic-term src/terminal_theme.rs @ 9129277 (src/terminal/theme_source.rs header, lines 1-17). Both deliberately leave NamedColor::Background unset so the window background follows the COSMIC theme via the WINDOW_BG_COLOR: AtomicU32 process-global (src/terminal/engine.rs:183, refreshed in src/app.rs:354-363).
• Config keys color_scheme_dark / color_scheme_light: String (defaults "COSMIC Dark" / "COSMIC Light", src/config.rs:16-17,104-106,143-144), resolved by name in app.rs:323-335 active_colors() using cosmic::theme::is_dark(); unknown names fall back to the matching built-in.
• In the settings UI these two keys are raw text fields in the Advanced section (src/settings.rs:83-86), not a picker.
• System light/dark flips already re-apply colors: DropTerm overrides both Application::system_theme_update and system_theme_mode_update (src/app.rs:1866-1883) → apply_config_to_tabs().
• Selection is rendered by swapping fg/bg (src/terminal/engine.rs:890,915) — same as cosmic-term (which carries a //TODO: better handling of selection).
• Deps in place: alacritty_terminal = "0.25.1", ron = "0.12", serde (Cargo.toml). cosmic-term additionally uses hex_color = "3" (MIT OR Apache-2.0) for #RRGGBB parsing.

Findings

1. cosmic-term: scheme model, storage, and application

All paths below are pop-os/cosmic-term @ master 3ef31d750d3b09a73f266923b0d64c5df038cf9f (2026-10-01; Cargo.toml says version 1.9.0, license GPL-3.0-only, alacritty_terminal = "0.25.1", cosmic-text = "0.19", hex_color = "3", ron = "0.11" — same engine and color-text stack as DropTerm).

Types (src/config.rs):

• ColorSchemeKind { Dark, Light } (L45-49) — every scheme is tagged with the mode it belongs to; the picker shows one list per kind (Dark/Light tabs).
• ColorSchemeId(pub u64) (L51-53) — opaque id, allocated as last_key_value().id + 1 on import (src/main.rs ColorSchemeImportResult, ~L2126-2146).
• ColorSchemeAnsi (L76-127) — black, red, green, yellow, blue, magenta, cyan, white: Option<HexColor>, with de_color_opt/ser_color_opt serde shims so the on-disk RON is a plain "#RRGGBB" string and missing fields are None (default, deny_unknown_fields, skip-if-empty on serialize).
• ColorScheme (L142-182) — name: String + foreground, background, cursor, bright_foreground, dim_foreground: Option<HexColor> + normal, bright, dim: ColorSchemeAnsi. This is exactly the “16 ANSI + fg/bg/cursor + bright/dim fg + dim table” set; there are no selection fields.
• AppTheme { Dark, Light, System } (L20-43) with fn theme() -> theme::Theme built from theme::system_dark()/system_light()/system_preference() plus a theme_type.prefer_dark(...) nudge.
• Config (L219-244) holds color_schemes_dark and color_schemes_light: BTreeMap<ColorSchemeId, ColorScheme> (user schemes live inside the cosmic-config entry, not as loose files), syntax_theme_dark / syntax_theme_light: String (selected scheme name per mode, defaults COSMIC_THEME_DARK/LIGHT), and per-profile overrides Profile::syntax_theme_dark/light (L188-217). Resolution: Config::syntax_theme(kind, profile_id) (L369-386); mode choice: Config::color_scheme_kind(&system_theme) (L295-307, honoring AppTheme). color_scheme_names() (L309-330) de-duplicates names (“Name (2)”) and sorts linguistically.

Conversion to alacritty colors (src/terminal_theme.rs):

• impl From<&ColorScheme> for Colors (L44-96): starts from auto_colors() (L12-42 — the ransid 256-color base: 6×6×6 cube for 16..=231 with v * 0x28 + 0x28 scaling, grays (v - 232) * 10 + 8 for 232..=255), then fills the NamedColor slots. None fields leave the slot None (alacritty_terminal falls back / warns at render).
• impl From<(&str, &Colors)> for ColorScheme (L98-146) — the export direction; export() (L258-290) round-trips and asserts equality over all color::COUNT slots before writing color-schemes/{name}.ron.
• Built-ins cosmic_dark()/cosmic_light() (L148-242) leave Background unset with the comment “Background comes from theme settings” (L188/L236). terminal_themes() (L245-256) returns just these two as HashMap<(String, ColorSchemeKind), Colors>.

The shipped RON files: the repo tree has 30 files under color-schemes/*.ron (COSMIC Dark/Light, Dracula, Gruvbox Dark, Solarized Dark/Light, Tango Dark/Light, Selenized ×4, Modus ×4, Rose Pine ×3, Pop Dark, Rxvt, XTerm, Linux Console, OneHalfDark, Everforest, Seashells, seal-brown-amber, …). Notably nothing in src/ reads that directory (grep for read_dir/include over the tree: zero hits) — at master they are an import source for users (Settings → Color Schemes → import file dialog, src/main.rs ~L2115-2150 ron::de::from_reader::<_, ColorScheme>) and the contribution point for new schemes (recent commits: “Add seal brown and amber terminal color scheme” f9d893b8, 2025-12-20). The two COSMIC RONs have no background field (matching the unset-Background behavior), while third-party ones like Dracula.ron set background: "#1e1f29".

Application at runtime (src/terminal.rs, src/terminal_box.rs):

• Terminal::set_config(config, color_scheme_kind, themes) (L642-703): looks up themes.get(&config.syntax_theme(kind, profile)), and if found copies any changed slot for i in 0..color::COUNT; then update_default_colors() rebuilds the cosmic-text Metadata (default cell bg/fg pair) and requests a redraw. Unknown scheme name → colors silently unchanged.
• WINDOW_BG_COLOR: AtomicU32 (L125) is the fallback when NamedColor::Background is None (convert_color, L129-140; effective_color, L388-399); the widget paints cell backgrounds from Metadata with opacity as alpha (terminal_box.rs ~L461-506) and reads the cursor color as colors[NamedColor::Cursor] (~L820-821).
• The app keeps themes: HashMap<(String, ColorSchemeKind), Colors> built by update_color_schemes() (src/main.rs L546-587): the two built-ins plus config-defined schemes; a custom scheme with a built-in’s name replaces it with a log::warn.

Light/dark switching (src/main.rs):

• Application::system_theme_update override (L3551-3557) forwards to Message::SystemThemeChange → update_config() (L673-710), which recomputes the scheme kind, refreshes WINDOW_BG_COLOR from theme.cosmic().background(theme.transparent).base, calls set_config on every terminal, and finishes with cosmic::command::set_theme(theme) for the toolkit palette.
• Import/export: ColorSchemeExport(…) opens a save dialog defaulting to {name}.ron and writes ron::ser::to_string_pretty(&color_scheme, PrettyConfig::new()) (L2000-2096).

Could DropTerm reuse a crate? No — ColorScheme lives in cosmic-term’s binary crate (not published), and there is no shared scheme crate; libcosmic’s cosmic-theme is the toolkit palette, not ANSI schemes. The options are vendor the ~150 lines of config.rs types + terminal_theme.rs conversions (DropTerm already vendored the palettes; both projects are GPL-3.0-only), or write a compatible struct from scratch.

2. alacritty_terminal 0.25.1: the color model we embed

From the local cargo registry (…/registry/src/index.crates.io-…/alacritty_terminal-0.25.1/src/term/color.rs, Apache-2.0):

• pub const COUNT: usize = 269 (L6) and pub struct Colors([Option<Rgb>; COUNT]) (L21-22) with Index<usize>/Index<NamedColor> (both Output = Option<Rgb>). Layout per its doc table (L8-20): 0..16 named ANSI, 16..232 color cube, 233..256 grayscale ramp (the table’s 233 is an upstream off-by-one in the comment; both ransid and alacritty fill 232..=255/256), 256 Foreground, 257 Background, 258 Cursor, 259..267 dims, 267 bright foreground, 268 dim background/dim foreground.
• NamedColor (vte 0.15.0 src/ansi.rs L1013-1072, re-exported as alacritty_terminal::vte::ansi): Black = 0 … White = 7, BrightBlack = 8 … BrightWhite = 15, Foreground = 256, Background, Cursor, DimBlack … DimWhite (259..266), BrightForeground, DimForeground (268). Rgb is the plain {r,g,b}: u8 struct from the same module.
• There is no List or TERM_FG/TERM_BG in the library crate — those are render-side concepts in the alacritty app crate: alacritty/src/display/color.rs has pub struct List([Rgb; COUNT]) built via fill_named/fill_cube/fill_gray_ramp from the config Colors (alacritty/src/config/color.rs, pub struct Colors at L9). Two details worth stealing if we ever derive values: DIM_FACTOR: f32 = 0.66 (dims are auto-derived as normal * 0.66 when unset, and dim_foreground defaults to foreground * 0.66), and alacritty’s cube uses r * 40 + 55 per channel while cosmic-term’s ransid base uses v * 0x28 + 0x28 (= *40 + 40) — a minor divergence that only affects indexed colors 16..=231.
• Selection is not a NamedColor — alacritty applies colors.selection = {text, background} at render time with CellForeground/CellBackground sentinels (see §3). cosmic-term/DropTerm instead swap fg/bg for selected cells (§1).

3. Alacritty’s colors: TOML format

Primary source: extra/man/alacritty.5.scd @ alacritty master (https://github.com/alacritty/alacritty/blob/master/extra/man/alacritty.5.scd, “# COLORS” section at L294+). Field inventory:

• colors.primary.{foreground, background, dim_foreground, bright_foreground} — bright_foreground only used when draw_bold_text_with_bright_colors; dim_foreground “automatically calculated based on the foreground color” when unset.
• colors.cursor / colors.vi_mode_cursor — {text, cursor}, each a hex color or the sentinels CellForeground/CellBackground; default { text = "CellBackground", cursor = "CellForeground" }.
• colors.search.{matches, focused_match} and colors.hints.{start, end} — {foreground, background} (search UI).
• colors.line_indicator, colors.footer_bar — {foreground, background}.
• colors.selection — {text, background} with the same sentinels; default swaps the cell colors.
• colors.normal / colors.bright / colors.dim — 8 named colors each (black, red, green, yellow, blue, magenta, cyan, white); “If the dim colors are not set, they will be calculated automatically based on the normal colors”.
• colors.indexed_colors — [{ index = <16..256>, color = "#…" }] overriding cube/ramp slots; colors.transparent_background_colors (L481) and colors.draw_bold_text_with_bright_colors (L489).
• Colors are strings #RRGGBB. draw_background does not exist in the current reference (0 hits in the scd); it was a legacy YAML-era key — transparency is window.opacity today. Don’t plan a config field around it.
• Theme files are imported via the top-level import = ["path.toml", …] key (L31-48; loaded in order, importing file last, missing files skipped). The official collection alacritty/alacritty-theme ships 177 TOMLs, Apache-2.0, each exactly # Colors (name) + colors.primary/normal/bright blocks (checked themes/gruvbox_dark.toml) — i.e. a scheme there is not required to define cursor/selection/dim.

4. Industry conventions for named schemes

Sources: kitty themes docs (https://sw.kovidgoyal.net/kitty/kittens/themes/ — mechanism, user-theme override by name in ~/.config/kitty/themes, auto light/dark section) and theme-file shape (kitty-themes repo, 413 .conf files; themes/Solarized_Dark.conf sets background/foreground/cursor/ selection_background/selection_foreground/color0-15 plus `## name:/## author:/

license:/## blurb:` metadata headers; option defaults in

kitty/options/definition.py L2523-2800). GNOME Terminal src/org.gnome.Terminal.gschema.xml @ gitlab master (keys and defaults quoted at L141-200, L315+, L346). iTerm2 https://iterm2.com/documentation-preferences-profiles-colors.html + a sample .itermcolors from mbadolato/iTerm2-Color-Schemes (key list above). Windows Terminal https://learn.microsoft.com/en-us/windows/terminal/customize-settings/color-schemes and fragment extensions (https://learn.microsoft.com/en-us/windows/terminal/json-fragment-extensions — a fragment scheme “must define a name … and every color in the color table”). base16: styling.md in chriskempson/base16 (role table) and tinted-theming/base16-schemes solarized-dark.yaml; the successor spec tinted8 (tinted-theming/home specs/tinted8/styling.md, 0.2.0-beta) adds variant: dark|light, scheme.slug, and inherits for syntax/ui.

Minimal-but-complete field set (the intersection everyone agrees on, plus what our engine can consume): name (+ ideally author/license metadata), foreground, background, 16 ANSI colors, cursor (cursor-text optional), and optionally selection fg/bg and dim/bright variants. cosmic-term’s ColorScheme = exactly this minus selection; alacritty’s = this plus search/hints/indexed; WT requires name + all 16 and treats cursor/selection as optional.

5. How a scheme list is usually shipped

Four patterns, all in active use:

1. Compiled-in built-ins — cosmic-term’s two hardcoded palettes; Windows Terminal’s schemes inside defaults.json; kitty’s embedded themes (overridable by a same-named file in ~/.config/kitty/themes). Pros: no I/O, versioned with the app, always present for fallback.
2. A repo of importable files — alacritty-theme (177 TOMLs), kitty-themes (413), cosmic-term’s color-schemes/ (30 RONs, imported via file dialog), iTerm2’s preset gallery. The app doesn’t scan them; users import.
3. User files auto-discovered from a config dir — kitty’s ~/.config/kitty/themes/*.conf (overrides builtins by theme name); WT fragments in defined locations. This is the hand-editable, dotfiles-friendly option.
4. Schemes stored inside the app config — cosmic-term’s color_schemes_dark/light maps in the cosmic-config entry (created via its editor UI or import); WT’s schemes[] in settings.json. No fs watching, atomic saves, but schemes aren’t shareable files without import/export.

freedesktop/XDG note: the only XDG-adjacent convention, terminal-colors.d(5) (util-linux 2.42.4, https://man.archlinux.org/man/terminal-colors.d.5.en), configures “output colorization for various utilities” — disable/enable/scheme files for CLI tools like dmesg, keyed per utility and $TERM*. It is consumed by util-linux utilities, not terminal emulators, and its scheme files map logical names (e.g. error`) to ANSI sequences — nothing to do with a 256-color palette. Do not adopt or claim compatibility with it for DropTerm’s scheme files. Emulator schemes have no standard location; the closest convention is “files in a subdir of the app’s XDG config dir” (kitty).

6. System light/dark mode + libcosmic (pinned rev 08a09e3)

Verified in the local checkout (~/.cargo/git/checkouts/libcosmic-41009aea1d72760b/08a09e3/, i.e. pop-os/libcosmic @ 08a09e3):

• cosmic::theme free functions (src/theme/mod.rs): active() L57, active_type() L63, is_dark() L77, system_dark() L88, system_light() L103, system_preference() L119 (reads ThemeMode::config from cosmic-config), ThemeType::prefer_dark L175.
• The Application trait hooks (src/app/mod.rs): fn system_theme_update(&mut self, keys: &[&'static str], new_theme: &cosmic_theme::Theme) -> Task<Message> (L470-476) and system_theme_mode_update(…, &cosmic_theme::ThemeMode) (L479-485), both default Task::none(). They are invoked from the runtime’s Action::SystemThemeChange handler (src/app/cosmic.rs:971, mode-gated at L961-964) and the mode-change path (src/app/cosmic.rs:1085-1102, which re-resolves theme::system_dark()/light() and calls both hooks). At this rev there is no window.theme_changed or Settings::theme callback — those names don’t exist in src/ (grep: zero hits); the hooks + core.system_theme() are the API.
• cosmic::command::set_theme(theme) (src/command.rs:36) switches the app-level toolkit palette; Core tracks system_theme / system_theme_mode.
• Reference apps: cosmic-term overrides system_theme_update → SystemThemeChange → update_config() (§1) — re-pick scheme kind by AppTheme, refresh WINDOW_BG_COLOR, re-set_config terminals, then set_theme. cosmic-edit (master) uses the same AppTheme {Dark,Light,System} + theme() helper in src/config.rs L14-33 and calls cosmic::command::set_theme(self.config.app_theme.theme()) on change (src/main.rs:725). kitty’s *-theme.auto.conf trio (§4) is the non-libcosmic precedent for the same UX: name a dark scheme and a light scheme once, follow the OS forever.

What applies to DropTerm

Recommended design (phased)

Phase 1 — named built-ins + picker (no new subsystems):

1. Adopt cosmic-term’s ColorScheme/ColorSchemeAnsi/ColorSchemeKind types (vendor ~150 lines from src/config.rs @ 3ef31d7, keeping the SPDX/copyright header like theme_source.rs already does). Field list is in §1; it is a strict superset of what dropterm’s engine consumes today and a subset of alacritty’s TOML, so importing alacritty-style themes later is lossless-ish (search/hints colors dropped).
2. Keep the conversion tail already vendored: add cosmic-term’s From<&ColorScheme> for Colors to theme_source.rs and route the existing cosmic_dark()/cosmic_light() through ColorScheme (their palettes are byte-identical to color-schemes/COSMIC Dark.ron / COSMIC Light.ron, which conveniently have no background field — preserving the follow-COSMIC-theme background behavior).
3. Ship a curated set of built-ins compiled in (include_str! + ron::from_str into a once_cell/const table, or code-generated). Directly reusable: the 30 RONs in cosmic-term’s color-schemes/ (GPL-3.0-only, same as DropTerm — see licensing below). A scheme with a background field overrides the COSMIC window background — that’s the desired behavior for e.g. Dracula; WINDOW_BG_COLOR remains the fallback for the two COSMIC schemes (and refresh_window_bg_color() already keeps it fresh).
4. UI: move scheme selection into the Appearance section as a dropdown (one choice for dark mode, one for light — or a single choice + “COSMIC Dark/Light for the other mode” if the settings spec prefers fewer rows). The existing color_scheme_dark/color_scheme_light: String config fields stay as-is — they already store the scheme name, and active_colors() already falls back gracefully on unknown names. That keeps DropTermConfig at #[version = 1] with no migration.
5. Light/dark: nothing to build. system_theme_update / system_theme_mode_update → apply_config_to_tabs() already re-resolve active_colors() on OS flips. (If an explicit app theme override is ever wanted, copy cosmic-edit/cosmic-term’s AppTheme tri-state + set_theme, and consult config.color_scheme_kind() instead of raw is_dark().)
6. Tests: round-trip ColorScheme ↔ Colors over all color::COUNT slots exactly like cosmic-term’s export() assert; unit-test name lookup, fallback-on-unknown-name, and that COSMIC built-ins leave Background unset.

Phase 2 — user schemes (pick one):

• Option A, config-stored (cosmic-term’s choice): BTreeMap<u64, ColorScheme> fields in the config, edited in a future scheme editor UI and/or RON import. No directory watching; atomic saves via cosmic-config; consistent with how everything else in DropTerm persists.
• Option B, directory-scanned (kitty’s choice): load $XDG_CONFIG_HOME/dropterm/color-schemes/*.ron at startup (and on config reload), later-wins/file-name-overrides builtins by scheme name. Better for dotfiles and hand-editing; needs a small loader + error surface (cosmic-term collects parse errors into color_scheme_errors shown in the UI).
• Either way, RON is the right format: it’s what cosmic-term exchanges, it matches the app’s serde-based config stack, and ron is already a dependency. Adding alacritty TOML import later is a small serde matter (parse colors: tables into the same struct).

Selection colors: leave out of v1 — cosmic-term has none either (fg/bg swap, with an upstream TODO). If added later, they are engine/widget-level (render-time override like alacritty’s selection {text, background}), not NamedColor slots, so the scheme struct can grow selection_foreground/background: Option<HexColor> without touching alacritty_terminal types.

Licensing

• cosmic-term: GPL-3.0-only (Cargo.toml, file headers). DropTerm is GPL-3.0-only (Cargo.toml L6, LICENSE) — copying its structs, conversion code, and the 30 RON scheme files is license-compatible. Keep the SPDX/copyright attribution header as theme_source.rs already does. Individual scheme designs upstreamed from elsewhere (Dracula — MIT, Solarized — Ethan Schoonover, Gruvbox, Rose Pine — MIT, Everforest — MIT, base16 schemes — various) are color values with metadata; cosmic-term ships them under its repo license, which is what we’d inherit.
• alacritty / alacritty_terminal: Apache-2.0 (the 0.25.1 registry tarball’s Cargo.toml says license = "Apache-2.0") — GPL-3.0-compatible if we port conversion logic or theme TOMLs from alacritty/alacritty-theme (repo license Apache-2.0, 177 themes).
• kitty-themes: each .conf carries its own ## license: header (e.g. Solarized Dark = MIT) — per-file compatible with GPL-3.0-only in the “MIT-licensed data” sense, but requires per-file checking; not the path of least resistance.
• mbadolato/iTerm2-Color-Schemes: mixed/unspecified per-scheme attribution — avoid as a bulk source.
• Deps: hex_color 3.0.0 = MIT OR Apache-2.0; ron 0.12 = MIT OR Apache-2.0.

Unverified / open questions

• Whether COSMIC packagers install cosmic-term’s color-schemes/ anywhere for users (no runtime consumer exists in the repo; packaging scripts were not inspected). Doesn’t affect the compiled-in recommendation.
• cosmic-term’s Colors doc-table says grays occupy “233..256” while both fillers use 232..=255/256 — upstream comment inconsistency only; slot 232 is the first gray either way. Harmless, but don’t copy the comment verbatim.
• Exact behavior when a config-selected scheme name disappears from the registry: cosmic-term keeps the previous Colors silently; DropTerm currently falls back to the COSMIC built-in. Either is defensible — pick one and pin it with a test.
• libcosmic’s in-flight “theme-v2” work (referenced in cosmic-term’s Cargo.toml patch comments) may change the cosmic::theme API at a future rev-pick; everything cited here is from the pinned 08a09e3.

Sources

• pop-os/cosmic-term @ 3ef31d750d3b09a73f266923b0d64c5df038cf9f (master, 2026-10-01): src/config.rs L20-49, L51-53, L76-182, L188-244, L295-330, L369-386; src/terminal_theme.rs (whole file, 290 lines); src/terminal.rs L125-140, L388-399, L642-710; src/terminal_box.rs L461-506, L820-821; src/main.rs L519-587, L673-710, L2000-2150, L2802-2812, L3551-3557; Cargo.toml; build.rs; color-schemes/ (30 files, incl. COSMIC Dark.ron, Dracula.ron) — https://github.com/pop-os/cosmic-term
• alacritty_terminal 0.25.1 (local cargo registry, Apache-2.0): src/term/color.rs L1-60 — plus vte 0.15.0 src/ansi.rs L1013-1072 (NamedColor)
• alacritty @ master: extra/man/alacritty.5.scd (COLORS section L294-490, import L31-48); alacritty/src/config/color.rs; alacritty/src/display/ color.rs (List, DIM_FACTOR) — https://github.com/alacritty/alacritty; themes: https://github.com/alacritty/alacritty-theme (Apache-2.0)
• kitty: themes kitten docs https://sw.kovidgoyal.net/kitty/kittens/themes/; kitty/options/definition.py L2523-2800; kittens/themes/main.py (CLI options); docs/remote-control.rst L180-184; theme files: https://github.com/kovidgoyal/kitty-themes (413 files; themes/Solarized_Dark.conf)
• GNOME Terminal @ gitlab master: src/org.gnome.Terminal.gschema.xml L141-200, L315-330, L346 — https://gitlab.gnome.org/GNOME/gnome-terminal
• iTerm2: https://iterm2.com/documentation-preferences-profiles-colors.html; sample .itermcolors from https://github.com/mbadolato/iTerm2-Color-Schemes (schemes/Solarized Dark Patched.itermcolors)
• Windows Terminal: https://learn.microsoft.com/en-us/windows/terminal/customize-settings/color-schemes and https://learn.microsoft.com/en-us/windows/terminal/json-fragment-extensions
• base16 / tinted: styling.md in https://github.com/chriskempson/base16; https://github.com/tinted-theming/base16-schemes (solarized-dark.yaml); https://github.com/tinted-theming/home specs/tinted8/styling.md
• util-linux: terminal-colors.d(5) (2.42.4) — https://man.archlinux.org/man/terminal-colors.d.5.en
• libcosmic @ 08a09e3 (DropTerm’s pinned rev, local cargo checkout): src/theme/mod.rs L50-135, L153-175; src/app/mod.rs L470-485; src/app/cosmic.rs L960-980, L1085-1110; src/command.rs L36 — https://github.com/pop-os/libcosmic/tree/08a09e3dfa1f729d52585fcedd6e731130235363
• cosmic-edit @ master: src/config.rs L14-33; src/main.rs L725, L1291-1329 — https://github.com/pop-os/cosmic-edit
• DropTerm local: src/config.rs, src/settings.rs, src/app.rs (L323-363, L1866-1883), src/terminal/theme_source.rs, src/terminal/engine.rs, Cargo.toml, LICENSE, ROADMAP.md