Fix excessive word spacing on Linux caused by emoji-font fallback - #3187
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Add Linux UI fonts (Ubuntu, Cantarell, Liberation Sans, DejaVu Sans) before the emoji fonts in the body font stack so the space glyph resolves from a text font instead of Noto Color Emoji's wide space glyph.
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ivan-ottinger
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Nice! 👍🏼 I can confirm the PR addresses the issue:
I did not observe any regressions on macOS / Windows.
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📊 Performance Test ResultsComparing 4759a62 vs trunk app-size
site-editor
site-startup
Results are median values from multiple test runs. Legend: 🟢 Improvement (faster) | 🔴 Regression (slower) | ⚪ No change (<50ms diff) |
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Related issues
How AI was used in this PR
AI-assisted: diagnosed the root cause (Chromium per-glyph font fallback picking up
Noto Color Emoji's wide U+0020 glyph on Linux because no text font earlier in the stack is installed there) and drafted the one-line insertion into the font stack. The change was reviewed by me before commit.Proposed Changes
Ubuntu,Cantarell,Liberation Sans,DejaVu Sans) to thebodyfont stack inapps/studio/src/index.css, positioned before the emoji fonts so a text font resolves first for the space glyph.-apple-system/BlinkMacSystemFont/Segoe UI).Why this fixes it
Chromium does per-glyph fallback in declared order. On Linux,
-apple-system,BlinkMacSystemFont,Segoe UI, and oftenRobotoaren't installed, so the first font that is installed used to beNoto Color Emoji— which has a very wide space glyph. Chromium would pick it up for U+0020 and stop, producing the gaps. TheNoto Sans/sans-serifentries already at the tail of the stack were never consulted because resolution had already terminated. Inserting Linux text fonts before the emoji fonts gives Chromium a real text font to resolve the space from.Testing Instructions
npm startand visually confirm type still renders in the system font and there is no additional spacing.npm startand visually confirm type still renders in the system font (SF Pro / -apple-system) — no regression.Before / After
Before:
After: normal inter-word spacing on Linux
Pre-merge Checklist