5.1.0

[Tyriar]

🚀 Features

Multiple texture atlas page support (#4244, #4252, #4274) via @Tyriar

Instead of there being a hard cap of 1024x1024 on the size of the texture atlas backing the canvas and webgl renderers, multiple textures are now supported. Each individual texture is now 512x512 which allows faster uploading to the GPU and will continually merge until the maximum of 4096x4096 is reached.

The benefits in simple terms of this change are:

• Less time from drawing a glyph to rendering it
• Less CPU is used when lots of glyphs are used
• Essentially unlimited space for glyphs, which is good for certain use cases but will also let us explore things like "perfect" dotted and curvy underlines in the future

Here is an example of a 512x512 texture atlas page right after the terminal has loaded and printed a powerline-based prompt:

And here is the 1024x1024 page after a lot of glyphs have rendered:

Slash and triangle custom glyphs (#4313) via @Tyriar

Eight new powerline extra custom glyphs are supported:

New option scrollOnUserInput (#4289) via @JasonXJ

You can now specify whether to scroll to the bottom of the terminal on user input, previously this was the default and only behavior. This new setting is enabled by default.

const term = new Terminal({ scrollOnUserInput: false });

🐞 Bug fixes

• Fix width of upper 1/8 block character (Fix width of upper 1/8 block char #4134) via @Tyriar
• Allow the renderer to be set before Terminal.open is called (Allow renderer to be set before Terminal.open is called #4151) via @Tyriar
• Fix trusted types in dom renderer (Fix trusted types in dom renderer #4157) via @Tyriar
• Fix several memory retention issues (Fix a bunch of memory retention problems #4185) via @Tyriar
• Remove check proposed api checks (Remove check proposed api checks #4204) via @silamon
• Clear the extended attribute on CSI 0 m via @JasonXJ
• Fix clipping of italic emoji (Fix clipping of italic emoji #4237) via @Tyriar
• Fix some edge cases in screenReaderMode (Fix a11y issues #4269 #4284) via @JasonXJ
• Send corresponding escape code for alt+space and ctrl+alt+space (Send corresponding escape code for alt+space and ctrl+alt+space #4290) via @JasonXJ
• Re-evaluate the link under the cursor instead dropping it completely when the terminal buffer changes (re-eval previous active link #4298) via @jerch

🏎️ Performance

• Optimizations to prevent blocking the main thread when resizing the buffer (some buffer handling optimizations #4115) via @jerch
• Reduce xterm.js start up time by deferring texture atlas warm up to an idle callback (Perform texture atlas warm up in an idle callback #4131) via @Tyriar
• Optimize canvas contexts for frequent reading (Optimize contexts for reading frequently #4137, Add willReadFrequently to canvas renderer too #4169) via @Tyriar
• Share rgba vars throughout Color.ts, fast setTheme parseColor (Share rgba vars throughout Color.ts, fast setTheme parseColor #4140) via @Tyriar
• Introduce new IdleTaskQueue and PriorityTaskQueue internal helpers (Do char atlas warmup via new IdleTaskQueue #4141, Use the browser's IdleDeadline to determine max task time #4143, Add PriorityTaskQueue #4144, Fix priority task queue and idle callback fallback #4155, Log a warning if task queues exceed deadline by 20ms #4293) via @Tyriar
• Defer paused renderer resize handling to idle callbacks (Defer paused renderer resize to idle callback #4142) via @Tyriar
• Optimize critical I/O path for input latency (Optimize critical I/O path for input latency #4145, Fix repetitive microtask problem #4153, Use microtask to flush the write buffer after input #4159, tweak buffering in server.js #4160, Capture data between terminal creation and connected to terminal in demo #4194) via @Tyriar, @jerch, @silamon
• Remove unnecessary clipping of texture atlas glyphs (Optimize _clipImageData #4200, Remove clipImageData completely #4201) via @Tyriar, @jerch
• Fix dropped frame issue caused by decorations (Fix dropped frame issue #4226) via @Tyriar
• Support multiple texture atlas pages (Support multiple texture atlas pages #4244) via @Tyriar

📝 Documentation and internal improvements

• Lint the codebase using putout (Lint using 🐊Putout: part 7 #4118) via @coderaiser
• Remove special publishing of v5 builds (Remove special v5 beta publishing #4123) via @Tyriar
• Correct comment on allowProposedApi (Update allowProposedApi comments #4125) via @BattlefieldDuck
• Move real-world uses section down (Move real-world uses section down #4152) via @dstein64
• Remove queueMicrotask polyfill (Remove queuemicrotask polyfill #4154) via @Tyriar
• General refactoring (Move w objects to $ prefix variables #4162, Split Utf8ToUtf32 decoder unit tests up #4179, Draw quads with triangle strip #4205, Improve names of IRenderDimensions interface members #4207, Re-enable onData event test #4209, Fix a bunch of TODOs #4210, Avoid passing circular callback into CoreService ctor #4301, Simplify options API  #4304, Remove ! to improve safety #4328) via @Tyriar
• Inline dirty row service into input handler (Inline dirty row service into input handler #4163) via @Tyriar
• Define all events and emitters consistently (Define all events and emitters consistently #4165, Revert "Merge pull request #4166 from Tyriar/event_with_emitter" #4177) via @Tyriar
• Bump copyright year (Bump copyright year #4176) via @Tyriar
• Lint rule for on=event emitter and rename all methods with on prefix to handle (Lint rule for on=event emitter and rename all methods with on prefix to handle #4187) via @Tyriar
• Create theme service (Create theme service #4188) via @Tyriar
• Switch CI agent to Ubuntu 20.04 (Switch to Ubuntu 20.04 #4192) via @silamon
• Fix webgl loading in the demo (Fix demo again #4193) via @silamon
• Create onSpecificOptionChange and onMultipleOptionChange helpers (Create onSpecificOptionChange and onMultipleOptionChange helpers #4195) via @Tyriar
• Add eslint-plugin-jsdoc with minimal comment rules (Add eslint-plugin-jsdoc with minimal comment rules #4206) via @Tyriar
• replit branding change (replit branding change #4211) via @hackermondev
• Revert decoration dispose changes (revert decoration dispose changes #4215) via @meganrogge
• Change clearing innerText to using replaceChildren to fix testing using jsdom (Change clearing innerText to using replaceChildren to fix testing using jsdom #4217) via @Nokel81
• Fix resize in demo (Fix resize in demo #4233) via @Tyriar
• Cache ICoreBrowserService.isFocused per task (Cache ICoreBrowserService.isFocused per task #4234) via @Tyriar
• Avoid GC pressure from server data buffer (Avoid GC pressure from server data buffer #4235) via @Tyriar
• Add console.image helper (Add console.image helper #4236) via @Tyriar
• Remove promise and fetch shims and use await for fetch (Remove promise and fetch shims and use await for fetch #4240) via @Tyriar
• Remove fill polyfill (Remove fill polyfill #4249) via @Tyriar
• New test buttons in the demo (Clear custom glyph test button sgr #4254, Add combo entries to sgr test for testing multiple sgr #4306, Add VT arrow buttons #4311, Add VT buttons through CSI P #4330) via @Tyriar
• Add custom keymap example to attachCustomKeyEventHandler docs (Add custom keymap example to attachCustomKeyEventHandler docs #4280) via @Tyriar
• Dev dependency updates (Update mocha #4286, Bump minimatch from 3.0.4 to 3.1.2 #4287) via @Tyriar, @dependabot
• Fix demo in Epiphany browser (fix demo in epiphany #4291) via @jerch
• Explain danger of XSS more explicitly with the linkHandler API (Improve explanation of danger with the linkHandler API #4310) via @Tyriar
• Point new issue questions at GH discussions (Point new issue questions at GH discussions #4312) via @Tyriar
• Allow scroll bar interaction in demo in screenReaderMode (Allow scroll bar interaction in demo in screenReaderMode #4315) via @Tyriar
• Explain object option edge case (Explain object option edge case #4322) via @Tyriar
• Improve IAttributeData jsdoc (Improve IAttributeData jsdoc #4327) via @Tyriar

🛑 Breaking changes

• There is a new allowNonHttpProtocols property on ILinkHandler which forces the embedder to opt-in to non-http(s) protocols. This is a breaking change in a minor release as it could improve security of embedders.

  // before 5.1.0
  const term = new Terminal({
    linkHandler: {
      ...
    }
  };
  
  // after 5.1.0
  const term = new Terminal({
    linkHandler: {
      // If you explicitly support and sanitize the links
      allowNonHttpProtocols: true,
      ...
    }
  };

🎉 New real-world use cases

• Super Terminal (Added application that uses xterm.js #4276) via @bugwheels94

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📥 Addons

xterm-addon-attach

• Warn/throw on unexpected attach addon socket state (Warn/throw on unexpected attach addon socket state #4208) via @Tyriar

xterm-addon-canvas

• Share texture atlases between the webgl and canvas renderers (Share texture atlas cache code between webgl and canvas renderers #4170, Ensure texture atlas comparison uses rgba not object #4168, Remove the canvas char atlas #4182) via @Tyriar
• Fix glyphs becoming garbled or invisible (Ensure stale bitmap is not used when drawing new characters #4189) via @Tyriar
• Disable canvas ImageBitmap optimization on Safari (Disable canvas ImageBitmap optimization on Safari #4219) via @Tyriar
• Correctly offset minimumContrastRatio check (Correctly offset mcr check on canvas renderer #4239) via @Tyriar
• Fix line height and letter spacing rendering (Fix line height and letter spacing on canvas renderer #4305) via @Tyriar
• Fix canvas renderer selection not re-rendering sometimes (Fix canvas renderer selection not re-rendering sometimes #4325) via @Tyriar

xterm-addon-serialize

• Fallback to default ansi colors when running xterm-headless (SerializeAsHTML(): Fallback to default ansi colors when running headless terminal #4196) via @silamon

xterm-addon-webgl

• Fix glyphs becoming garbled or invisible (Fix clearTextureAtlas call as implemented on IRenderer #4180, Fix race condition that could when clearing atlas on 2+ terminals #4181) via @Tyriar
• Share texture atlases between the webgl and canvas renderers (Share texture atlas cache code between webgl and canvas renderers #4170, Ensure texture atlas comparison uses rgba not object #4168, Remove the canvas char atlas #4182) via @Tyriar
• Enable the webgl renderer on safari 16 and above (Enable the webgl renderer on safari 16 and above #4255) via @Tyriar
• Fixes disappearance of characters in webgl renderer (Fixes disappearance of characters in webgl renderer #4271) via @jeanp413
• Fix NPE in webgl renderer (Fix NPE in webgl renderer #4326) via @Tyriar

xterm-addon-web-links

• Major rework of the addon (Fix weblinks #4288) via @jerch. This adds support for more URLs, fixes underlines sometimes being incorrect and changes the regex. There will be regressions in previous behavior with this but overall it's in a much better state. If you find any problems please report them to us.
• Add 1024 character limit (Add 1024 character limit to web links addon  #4251) via @Tyriar

🤝 Compatible addon versions

• xterm-addon-attach@0.7.0
• xterm-addon-fit@0.6.0
• xterm-addon-ligatures@0.6
• xterm-addon-search@0.10.0
• xterm-addon-serialize@0.9.0
• xterm-addon-unicode11@0.4.0
• xterm-addon-web-links@0.8.0
• xterm-addon-webgl@0.14.0

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This discussion was created from the release 5.1.0.