xterm3 6.1.2

Maintained Flutter terminal emulator package with fast rendering and broad VT/xterm compatibility.

6.1.2 - 2026-08-09

• Terminal.onReply separates the data the terminal sends on its own initiative — device attributes, status and cursor-position reports, colour and size queries, terminfo capabilities, focus reports, OSC 52 clipboard reads — from the data the user types. Both have always travelled the same wire, and the bytes cannot be told apart after the fact: an arrow key and a cursor-position report are both an escape sequence. An embedder that reads traffic as "the user is typing", or that mirrors one session across two terminals and must not answer a query twice, needs the distinction. Replies fall back to onOutput when no reply sink is set, so nothing changes for existing callers.

6.1.1 - 2026-08-09

• TerminalView.commitComposing() emits a pending IME composition as terminal input and reports whether there was one. Input that reaches the terminal from outside the keyboard — a mobile extra-keys bar, a paste button — is appended to what the terminal has already received, but an open composition has not been received yet: it is deferred until the composition resolves. Sending Tab while the IME still holds www completed an empty line rather than www. Callers should commit before such a key; resetEditingState() remains for when the composition is genuinely to be thrown away.
• Fixed an out-of-band commit being typed twice in deleteDetection mode. The guard that swallows the IME's delayed echo of a committed composition existed only on the non-deleteDetection path, so on Android — where terminals turn deleteDetection on to keep backspace working — pressing Enter sent the command and then the keyboard's own delayed commit replayed the whole word on the next line. The guard now covers both paths and is spent on the very next editing value, so the same word typed again later is still genuine input.

6.1.0 - 2026-08-08

• TerminalView.predictionText draws caller-supplied text at the cursor, underlined, without it ever entering the buffer. It exists for clients that can show a keystroke before the far end confirms it — a Mosh client's local echo, say — where writing the character into the buffer would be wrong, because a screen diff computed against the frame the server believes you have will never repair a locally invented cell.
• The text is suppressed while IME composition is active: a user composing a character must not also be shown a speculative one.
• It is drawn whenever the cursor's row is on screen, not when the cursor itself is painted, so it stays readable through the cursor's blink-off phase and while an application has hidden the cursor. Composition keeps its old behaviour of forcing the cursor visible; predictions deliberately do not.

6.0.1 - 2026-08-06

• No library changes. The published archive drops from 5 MB to 377 KB: 6.0.0 shipped the example app's 4 MB suggestion corpus, the benchmark inputs under script/, a bundled font and the README screenshots, none of which anyone depending on the package has a use for. The README still renders its images on pub.dev, which links them from raw.githubusercontent.
• Move docs/ to doc/, the directory name pub's layout conventions expect.

6.0.0 - 2026-08-06

• Renamed the package from xterm2 to xterm3. The code has diverged far enough from the xterm2 line — renderer, buffer and reflow, input and search — that it continues under its own name at klc/xterm3. The public API is unchanged, so migration is mechanical:

  • xterm2: ^5.3.0 becomes xterm3: ^6.0.0 in pubspec.yaml.
  • package:xterm2/... becomes package:xterm3/... in imports. The entry point keeps its name: import 'package:xterm3/xterm.dart';.
  • XTERM2_FUZZ_ROUNDS becomes XTERM3_FUZZ_ROUNDS.

• Relicensed from MIT to AGPL-3.0-or-later. From this release on, an application that links xterm3 is a covered work: distributing it, or letting users interact with it over a network, requires offering the complete corresponding source under the AGPL. The MIT-licensed xterm / xterm2 work this package derives from keeps its terms — the notice is in LICENSE.MIT and NOTICE — and xterm2 5.3.0 and earlier remain MIT.

• Make plain-text http(s):// and www. URLs clickable, not just OSC 8 hyperlinks. Terminal.urlAt(CellOffset) detects a URL in buffer text (soft-wrap aware, joined the same way Terminal.search joins wrapped rows) and TerminalView.onHyperlinkTap now fires for it too. On desktop this follows the existing OSC 8 convention — hold Cmd (macOS) or Ctrl and click, with a hover underline — while touch has no modifier to hold, so a direct tap opens the link. Terminal.search and the new detector now share one logical-line/cell-mapping implementation (terminal_logical_line.dart) instead of duplicating it.

• Add PacedTerminalWriter, an opt-in way to feed PTY output to a terminal a frame's worth at a time. Writing every chunk as it arrives lets a burst own the UI thread between frames: 32 MiB of cat-style output on a 170x50 grid drains in 566ms at 37 frames per second. Through the writer with its default 8ms budget, the same burst takes 854ms and holds 75 frames per second. It is a trade — around 50% slower to drain, smooth while it drains — so nothing uses it by default.

• Allocate less slack per buffer line. Line storage rounded its capacity up by doubling from 64, so a 170-column line reserved 256 cells and never addressed half of them. Scrolling allocates one line per line of output, so that slack was charged on the hottest path in the terminal. Capacity now rounds up to a multiple of 32, which still absorbs the small widenings a resize does: 12% more throughput on ordinary output and 16% on long lines.

• Batch writes for alphabets other than English. The parser wrote a run of printable ASCII into cells in one go and handed everything else to the per-code-point path, so the first accented letter ended the run and a language written entirely in non-ASCII letters never batched at all — Cyrillic ran at 6 MiB/s, a fifteenth of ASCII. Runs are now defined by isSingleCellPrintable: ASCII, Latin-1, Latin Extended-A and B, IPA, spacing modifiers, Greek, Cyrillic and Armenian, each of which is width 1 and cannot continue a grapheme cluster. Cyrillic 6 to 73 MiB/s, Turkish 32 to 54.

• Roughly double the throughput of non-ASCII text. Grapheme cluster detection had a fast path only for the case where both the previous cell and the incoming code point are ASCII, so a single accented letter — ö in Turkish, any Latin-1 word — dropped every following character into full grapheme segmentation, at two string allocations and two segmentation passes each. Nothing below U+0300 can continue a cluster, so that is now the cut, and writeChar skips both cluster checks for such code points. Measured with bin/parse_bench.dart: 15 MiB/s to 32 MiB/s on Turkish text, against a 35 MiB/s ceiling with grapheme clustering disabled entirely.

• Add bin/parse_bench.dart, which measures write-path throughput with no Flutter and no renderer, separating the parser from the buffer writes it drives.

• Stop the procedural glyph cache from making large terminals slower than no cache at all. Its keys are (codepoint, cell size, colour), so a screen drawing box lines in many colours can reference thousands of distinct keys, and at the old 512-entry capacity a full-screen grid thrashed it — a miss pays for the recording and the insert on top of the drawing, so the cache cost 1.9ms of UI time per frame over painting uncached. Capacity is now 4096. Block elements (U+2580..U+259F), which are one or two drawRect calls, now bypass the cache entirely: replaying a recorded picture per cell put a picture boundary in the raster command stream for every cell and cost 0.4ms of raster per frame at a 100% hit rate, for no saving on the UI thread.

• Fix wide characters corrupting the cell grid. BufferLine.setCell now repairs the width-2 lead / width-0 placeholder pairing itself, so no caller can leave half a wide character behind — a filler cell written when a wide character does not fit before the right margin used to overwrite an existing placeholder in place, and growing a previously shrunk line could resurrect a stale lead whose placeholder was cut off. Found by the new parser fuzz harness.

• Defer soft-keyboard input while an IME composition is open, in both deleteDetection modes, so Turkish and CJK text reaches the terminal only once the keyboard commits it. Previously an uncorrected preview (gg before ğıİşçöü, ni before nihao) was written to the terminal as literal text. Composition is now tracked by composing-range identity rather than length, which keeps single keypresses that Android keyboards wrap in a never-collapsing composing range landing exactly once.

• Recognise a backspace at offset 0 as a delete when deleteDetection is off. It previously produced an empty insert and no delete ever reached the terminal.

• Add an opt-in Terminal.onUnknownSequence diagnostic callback, reporting ESC, CSI, OSC and DCS sequences the parser does not recognise. It costs nothing when unset, and deliberately stays silent for sequences that are handled internally.

• Behavior change: Observable.listeners is now an Iterable<void Function()> view instead of a Set<void Function()>. Iterating, length and contains keep working; code that mutated the set directly must call addListener and removeListener instead. The backing storage is now an append-only list with tombstoned removals, so notifyListeners no longer allocates a defensive copy on every notification — it ran once per Terminal.write.

• Cache rasterised procedural glyphs (box drawing, block elements, Powerline, Braille) as ui.Picture keyed on code point, cell size and colour. They were re-tesselated as vector paths on every repaint, including on a static screen.

• Replace the paragraph cache's O(n log n) eviction with a lazily repaired binary min-heap. Eviction previously copied and sorted every entry once per batch; the cache-hit path stays allocation-free and untouched.

• Prune OSC 8 hyperlink URIs when scrollback lines are evicted, instead of only when the registry hits its ceiling. Eviction scans are batched so hyperlink heavy output does not pay a full buffer scan per evicted line.

• Assert that Terminal.write is not re-entered. Re-entering it from a listener or an onOutput/onBell/onTitleChange callback corrupts parser state.

• Deprecated: EscapeHandler.unkownEscape is superseded by the correctly spelled unknownEscape. The old name still works and forwards to the new one; it will be removed in the next major.

• Deprecated: CellData.getHash is unused inside the package and will be removed in the next major.

• BufferLine.data is deprecated and marked @visibleForTesting; it exposed raw cell storage for mutation. BufferLine.anchors now returns an unmodifiable live view.

• Add a seeded parser fuzz harness and assert real invariants in the stress test, which previously only checked that nothing threw. Two pre-existing bugs the harness uncovered — a RangeError in resize reflow and a wide character left in a line's last column without room for its placeholder — are recorded as skipped regression tests pending a fix.

• Behavior change: TerminalController now defaults to PointerInputs.all(), so pointer motion and drag events reach the terminal. Applications that enable DEC private modes 1002 (button-event tracking) and 1003 (any-event tracking) now receive mouse reports out of the box, matching xterm, iTerm2 and Kitty. Reports are still gated on the mouse mode the application requests, so a terminal with mouse reporting disabled emits nothing. To restore the previous default, pass TerminalController(pointerInputs: PointerInputs({PointerInput.tap, PointerInput.scroll})).

• Render font ligatures when TerminalStyle.enableLigatures is set, keeping the cell grid intact by falling back to per-cell painting whenever a shaped run would not fill exactly the cells it covers. Requires a font that ships ligatures, such as Fira Code, JetBrains Mono or Iosevka.

5.3.0 - 2026-07-28

• Render bounded search matches with a distinct active result.
• Auto-scroll scrollback while extending a selection beyond the viewport.
• Add Shift+Home/End/PageUp/PageDown scrollback navigation.
• Track primary OSC 133/633 prompts across scrollback and reflow.
• Navigate semantic prompts with native platform shortcuts.
• Correct modified arrow-key sequences across main and alternate screens.
• Encode modified F1–F4 keys with xterm-compatible CSI sequences.
• Preserve Shift+wheel scrollback while applications report mouse input.
• Report horizontal wheel gestures and simulate them in alternate screens.
• Keep application scrolling active when Flutter replaces its scroll position.
• Preserve active and saved cursor positions through resize reflow.
• Leave double- and triple-click handling to applications using mouse tracking.
• Complete application mouse drags with release events without host selection.
• Report mouse buttons immediately without gesture-recognizer delays.
• Report back and forward mouse buttons through extended mouse protocols.
• Ignore unsupported highlight tracking without disrupting active mouse input.
• Respond to legacy DECID terminal identification requests.
• Report the current xterm3 version to terminal applications.
• Preserve complete semicolon-rich OSC titles, paths, and cursor names.
• Render the British national replacement character set.
• Render text decorations consistently across blank cells.
• Ignore orphaned zero-width marks instead of altering existing cells.
• Preserve combining marks after changing grapheme-cluster mode.
• Let wide symbol glyphs use adjacent blank cells instead of clipping.
• Keep IME composition text on the active row near the right edge.
• Preserve Ctrl+A and Ctrl+V input with standard terminal clipboard shortcuts.
• Preserve AltGr-composed text on Windows and Linux keyboards.
• Encode modified Enter keys distinctly for modern interactive CLIs.
• Preserve distinct Ctrl+Shift letter chords with fixterms encoding.
• Add standard Ctrl+Insert copy and Shift+Insert paste shortcuts.
• Correct Ctrl+Alt+Backspace and DEC backarrow modifier handling.
• Encode modified Escape keys distinctly for interactive applications.
• Preserve legacy Ctrl+number-row control chords.
• Bound streaming clipboard capture memory and recover after overflow.
• Reduce allocation overhead for non-ASCII terminal output.
• Avoid duplicate Unicode width lookups while processing terminal output.
• Preserve supplementary Unicode glyphs split across output chunks.
• Reduce memory overhead when sanitizing unsafe paste payloads.
• Release consumed terminal input buffers without waiting for more output.
• Ignore unsupported control bytes instead of rendering them as glyphs.
• Harden hyperlink hit testing during concurrent resize and reflow.
• Update hovered OSC 8 links immediately when the platform modifier changes.

5.2.0 - 2026-07-25

• Harden resize behavior for synchronized output, tab stops, and size reports.
• Reduce parser, allocation, and cell-copy overhead during dense TUI output.
• Allocate scrollback cell metadata lazily to reduce idle memory use.
• Match modern terminal handling for Alt-modified text input.
• Expose complete OSC 3008 hierarchical context metadata.
• Add bounded Unicode-aware scrollback search across soft wraps.

5.1.0 - 2026-07-19

• Add Unicode 17 width handling and broader emoji grapheme support.
• Add Kitty keyboard modifiers and expanded VT/xterm protocol compatibility.
• Improve OSC 8 hyperlinks, selection isolation, clear behavior, and inline TUI scrolling.
• Expand procedural rendering for box drawing, blocks, mosaics, branch graphs, and legacy symbols.
• Improve glyph fallback, wide-character rendering, contrast, and decoration accuracy.
• Reduce parser, resize, repaint, and paragraph-cache overhead under sustained output.
• Harden resize reflow and buffer editing across wrapped and wide lines.

5.0.0 - 2026-07-11

• Rename package to xterm3 for the maintained fork.
• Support DEC synchronized updates with Alacritty-compatible timeout recovery.
• Report terminal view focus changes for DEC focus tracking mode.
• Render application-selected DECSCUSR cursor shapes.
• Animate blinking cursors with Alacritty-compatible interval and timeout.
• Bound OSC payload memory and safely discard oversized fragmented sequences.
• Bound CSI payload and parameter memory across fragmented sequences.
• Expose authoritative current-directory updates from OSC 7.
• Parse, render, hit-test, and activate bounded OSC 8 hyperlinks.
• Render common block and box-drawing glyphs procedurally without font seams.
• Reuse cell paints to reduce per-frame rendering allocations.
• Keep the full viewport available when maxLines is smaller than its height.
• Improve terminal glyph rendering, prompt symbols, OSC hyperlinks, cursor visibility, and scroll behavior.

4.0.0 - 2024-02-27

• Update for Flutter 3.19 #190. Thanks @domesticmouse.
• Fix designate charset logic #186. Thanks @djnalluri.

3.6.1-pre - 2023-04-28

• Add Termianl.onPrivateOSC callback
• Copy shortcut on Windows default to Ctrl+Shift+V (#173)

3.6.0-pre - 2023-04-27

• Basic ZMODEM support

3.5.0 - 2023-04-20

• Support customizing word separators for selection #160. Thanks @itzhoujun.
• Fix incorrect tab stop handling #161. Thanks @itzhoujun.
• Added support for Ctrl+Home, Ctrl+End etc #169. Thanks @nuc134r.

3.4.1 - 2023-01-27

• Fix Flutter 3.7 incompatibilities #151, thanks @jpnurmi.

3.4.0 2022-11-4

• Mouse input is enabled by default.
• Support scrolling in alternate buffer.
• Fix deleteLines behavior.
• Fix eraseDisplayFromCursor removes characters before the cursor.

3.3.0 - 2022-10-30

• Sync ShortcutManager's shortcuts in didUpdateWidget #140, thanks @jpnurmi.
• fix: terminal font size not respecting system level font scale #138, thanks @LucasAschenbach.
• Fix selection color #135, thanks @jpnurmi.
• fix: dispose controllers of TerminalView #132, thanks @tauu.
• feat: add hardwareKeyboardOnly flag to TerminalView #131, thanks @tauu.
• feat: initial mouse support #130, thanks @tauu.
• feat: limited window manipulation support #129, thanks @tauu.
• fix: workaround to draw underlined spaces #128, thanks @tauu.
• feat: block selection #127, thanks @tauu.
• feat: enable changing the inputHandler of a terminal #126, thanks @tauu.
• fix: export TerminalTargetPlatform #125, thanks @tauu.
• fix: only dispose the FocusNodes which TerminalView creates #124, thanks @tauu.
• feat: expose readOnly flag of CustomTextEdit in TerminalView #123, thanks @tauu.
• fix: supports numpad enter key #137.
• feat: expose reflowEnabled flag #104.
• docs: add virtual keyboard example #141.

3.2.7 2022-9-13

• Fix lint issues.

3.2.6 2022-9-13

• First stable release of xterm.dart v3.

3.2.6-alpha 2022-9-13

• Fix new line width in reflow.

3.2.5-alpha 2022-9-12

• Fix intent related issue.

3.2.4-alpha 2022-9-12

• Use flutter native shortcut intents.

3.2.3-alpha 2022-9-12

• Export shortcut related classes.

3.2.2-alpha 2022-9-12

• Implement default keyboard shortcuts.

3.2.1-alpha 2022-9-12

• Disable optional line scroll mode that is under development.

3.2.0-alpha 2022-9-12

• Enhanced selection handing.
• More tests.

3.1.0-alpha 2022-9-4

• Update dependencies & merge into master

3.0.6-alpha 2022-4-4

• Export TerminalViewState
• Added onTap callback to TerminalView

3.0.5-alpha 2022-4-4

• Avoid resize when RenderBox.size is zero.
• Added charInput and textInputmethod.
• Added requestKeyboard, closeKeyboard and hasInputConnectionmethod.
• Export KeyboardVisibilty

3.0.4-alpha 2022-4-1

• Improved text editing
• Added composing state painting
• Adapt to MediaQuery.padding

3.0.3-alpha 2022-3-28

• Improved scroll handing
• Improved resize handing
• Fix focus repaint
• Fix OSC title update

3.0.2-alpha 2022-3-28

• Re-design KeyboardVisibilty

3.0.1-alpha 2022-3-27

• Add KeyboardVisibilty

3.0.0-alpha 2022-3-26

• Initial release of v3.

2.6.0 - 2021-12-28

• Add scrollBehavior field to the TerminalView class #55.
• Feature: Search #60. Thanks @devmil.
• Fixes for occasional unintended multi character input #61. Thanks @devmil.
• Fixes ALT + L for a Mac (German Layout) #62. Thanks @devmil.
• Fixes example build problem of flutter-windows for new version of flutter #63. Thanks @linhanyu.
• Fixes inverse color text (when background == 0) #66. Thanks @devmil.
• Fixes assert of scrollController.position #67. Thanks @linhanyu.
• Change interface of ssh.dart example to satisfied new dartssh #69. Thanks @linhanyu.
• add configuration options for keyboard #74. Thanks @jda258.
• Adds check if the TerminalIsolate has already been started #77. Thanks @devmil.

2.5.0-pre 2021-8-4

• Support select word / whole row via double tap #40. Thanks @devmil.
• Adds "selectAll" to TerminalUiInteraction #43. Thanks @devmil.
• Fixes sgr processing #44,#45. Thanks @devmil.
• Adds blinking Cursor support #46. Thanks @devmil.
• Fixes Zoom adaptions on non active buffer #47. Thanks @devmil.
• Adds Padding option to TerminalView #48. Thanks @devmil.
• Removes no longer supported LogicalKeyboardKey #49. Thanks @devmil.
• Adds the composing state #50. Thanks @devmil.
• Fix scroll problem in mobile device #51. Thanks @linhanyu.

2.4.0-pre 2021-6-13

• Update the signature of TerminalBackend.resize() to also receive dimensions in pixels(#39). Thanks @michaellee8.

2.3.1-pre 2021-6-1

• Export theme/terminal_style.dart

2.3.0-pre 2021-6-1

• Add import 'package:xterm/isolate.dart';

2.2.1-pre 2021-6-1

• Make BufferLine work on web.

2.2.0-pre 2021-4-12

2.1.0-pre 2021-3-20

• Better support for resizing and scrolling.
• Reflow support (in progress #13), thanks @devmil.

2.0.0 2021-3-7

• Clean up for release

2.0.0-pre 2021-3-7

• Migrate to nnbd

1.3.0 2021-2-24

• Performance improvement.

1.2.0 2021-2-15

• Pass TerminalView's autofocus to the InputListener that it creates. #10, thanks @timburks

1.2.0-pre 2021-1-20

• add the ability to use fonts from the google_fonts package #9

1.1.1+1 2020-10-4

• Update readme

1.1.1 2020-10-4

• Add brightWhite to TerminalTheme

1.1.0 2020-9-29

• Fix web support.

1.0.2 2020-9-29

• Update link.

1.0.1 2020-9-29

• Disable debug print.

1.0.0 2020-9-28

• Update readme.

1.0.0-dev 2020-9-28

• Major issues are fixed.

0.1.0 2020-8-9

• Bug fixes

0.0.4 2020-8-1

• Revert version constrain

0.0.3 2020-8-1

• Update version constrain

0.0.2 2020-8-1

• Update readme

0.0.1 2020-8-1

• First version