Appearance Themes

Choose a Theme

Settings → Appearance has separate light/dark theme areas, four cards per row that grow with window width. Aster includes 9 light and 15 dark themes aligned with Otty 1.3.1. Selection updates the workspace and open terminals immediately without closing Settings, switches to the theme's light/dark appearance, and enables an independent dark theme when choosing dark.

View → Theme offers a searchable picker containing all 24 themes. Arrow keys or hovering preview the Tabs Sidebar, title bar, and Container holding central Panes and the Inspector. Click/Return saves and changes appearance; Esc, clicking outside, or switching apps cancels and restores the previous theme.

Glass Light/Dark retain actual theme transparency, using native macOS materials to show the desktop. Screenshot gray is the composited result, not a saved flat color. All splits update together. Floating Card, Nord, Pink, Monokai Classic, and other themes use their own cursor-text and selection colors rather than generic approximations. The nine light themes apply final detail values to Window, Container, Sidebar, tab bar/tabs, terminal, Inspector, cursor, selection, and ANSI colors. The Inspector and central Pane share one Container card without a second Sidebar material. Undefined light-theme selection defaults to terminal foreground at 30% opacity.

Dark themes also apply to Pane toolbars, find bars, Sidebar, and Inspector. Terminal-only themes such as Tokyo Night/Dracula derive a slightly lighter Sidebar from their background rather than one common black-gray. File Pane toolbars do not remain white.

Edit Theme Colors

1. Select a card; light cards set the light theme and dark cards the dark one. Adjust fonts, cursor color, and opacity below; empty cursor color follows the theme. Import .astertheme or open the theme folder there. Settings itself follows system appearance, not terminal theme colors.
2. Details show a terminal sample, foreground/background, ANSI 16 colors, and Window/Panel/Tab/Cursor/Selection tokens. Click a color/token to open its editor at that field, or expand all parameters with the edit-theme action. #RRGGBB / #RRGGBBAA applies when leaving the field. Color/ANSI/theme-font edits keep the name/ID and append managed overrides to the original theme. Only explicit Duplicate creates a new theme.
3. Restore Theme's Original Parameters clears color/ANSI/font overrides without deleting the theme file. Mappable values sync to its managed-override section. Failure retains the in-app values and shows the actual error.

Import Themes

Import Theme… accepts regular .astertheme files up to 256 KiB, not symlinks/FIFOs/devices, validating name and all ANSI 16 colors first. Open the theme folder at ~/.config/aster/themes for built-in, edited, and imported text files. First launch copies 24 bundled themes there. Aster neither reads nor writes ~/.config/otty/themes; .astertheme and .ottytheme stay independent.

Text and Fonts

Text controls adjust size, bold, italic, underline, blink, ligatures, smoothing, and line height immediately in open terminals; menu font-size actions update immediately too. Line height changes grid height/space. In ordinary/GPU drawing, bar cursors use the actual font size, vertically centered in the cell, without extending into the previous line through font leading or sitting too low in Shell/Agent inputs. Old cursor pixels clear every frame so style changes/typing leave no cell trails.

Font Family has four scopes; enter a name directly or clear it to restore auto/inheritance. Install/open-font-folder actions are available:

• Computed Value: read-only actual regular/bold/italic/bold-italic resolved through Global → Theme → Fallback; system fonts are labeled system monospace.
• Global: takes priority over theme. An unset primary continues to use the theme. Automatic weight/style matching hides per-style pickers; turn it off for separate faces.
• Theme: overrides the current theme. The primary goes first in font-mono while preserving other candidates; style fonts use font-mono-bold, font-mono-italic, and font-mono-bold-italic. Built-ins retain name/ID without duplication. The full candidate stack remains editable.
• Fallback: fills missing characters with regular/bold/italic/bold-italic choices; unspecified styles inherit regular fallback. Aster Nerd Symbols keeps Powerline/Nerd icons visible. Ordered fallbacks follow the primary, with the system language's default CJK font appended (PingFang SC for Simplified Chinese), preventing symbol-dependent regional glyph changes. Set regular fallback to choose another CJK font.

With only a regular font and automatic matching, Aster finds styles in its family, falling back safely to regular if absent. JetBrains Mono 2.304 ships/registers at startup; no system installation is needed. Missing custom names remain in the field without rewriting, while rendering falls back to macOS Menlo Regular and Computed Value shows that result. Nerd-patched family names differ, such as JetBrainsMono Nerd Font versus JetBrains Mono; use the actual listed name.

Cursor

Cursor controls include theme/custom color, text-under-cursor color, opacity, block/bar/underline/hollow-block shape, blink priority, and smooth animation, with live preview.

• Default Off/On sets initial blink; vim, Claude Code, Codex, and others can later request blink via DECSCUSR, but cannot override your chosen shape.
• Always Off/On fixes blink too and ignores program requests.

Agent output retains cursor shape but pauses blinking, restoring the chosen policy at awaiting-input/completion. Panes without keyboard focus (inactive split Panes and Panes in unfocused windows) show no cursor and leave no hollow box; the cursor returns in your chosen shape on focus. Bar cursors and hollow-block outlines are fixed at 2 pixels wide. IME composition and password-input indicators are unaffected. Smooth animation affects only short same-line movements and respects macOS Reduce Motion.

Dock Icon

The card previews the app's Dock icon. Spin While Task Is Running rotates only the central star, leaving the rounded base and > still. Its continuing CPU/power cost makes it off by default. Turn Red on Error changes the base red with !; clicking focuses the failed tab and acknowledges it. Without red state/new errors, clicking just returns to the last tab. Bounce on Notification applies only when Aster is backgrounded and system permissions allow, continuing until you return. The three switches are independent.