fix(terminal): enable touch-scroll in alternate buffer with mouse tracking#383
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…cking For providers with the native scrollInputPolicy (the default), touch swipes in alternate buffer + mouse-tracking mode formerly fell through to scrollLines, which is a no-op in xterm.js alternate buffers because they have no scrollback. Fix: when native policy is active and the terminal is in alternate buffer with mouse tracking on, dispatch synthetic WheelEvents directly to term.element. xterm.js translates these into mouse-wheel CSI sequences sent to the PTY, matching desktop wheel behavior. Includes position data (clientX/clientY) on synthetic events for accurate mouse tracking in TUIs with multiple scrollable regions. Tests cover: - Native policy wheel dispatch (upward and downward direction, multi-line swipes producing repeated events, correct deltaMode). - term.element == null fallback to scrollLines. - Fallback-to-cursor-keys policy sends cursor key sequences. - Normal buffer continues to call scrollLines as before.
danshapiro
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Jun 2, 2026
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For providers with the native scrollInputPolicy (the default), touch swipes in alternate buffer + mouse-tracking mode formerly fell through to scrollLines, which is a no-op in xterm.js alternate buffers because they have no scrollback.
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Passed 4th review (3rd after fixes).