Merge pull request #397 from irisitymichaelgrundberg/fix/detached-session-owns-its-pane-size

fix(terminal): let a detached session's own window own its pane size

src/web/public/terminal-ui.js

@@ -940,7 +940,10 @@ Object.assign(CodemanApp.prototype, {
         // causes Ink to re-render at the new row count, garbling terminal output.
         // Local fit() still runs so xterm knows the viewport size for scrolling.
         const keyboardUp = typeof KeyboardHandler !== 'undefined' && KeyboardHandler.keyboardVisible;
-        if (this.activeSessionId && !keyboardUp) {
+        // Same yield as sendResize: never resize a PTY whose session is showing
+        // in its own window. Dragging the dashboard's border must not reshape it.
+        const detachedElsewhere = !this.isSoloWindow && this.detachedSessions?.has(this.activeSessionId);
+        if (this.activeSessionId && !keyboardUp && !detachedElsewhere) {
           const dims = this.fitAddon.proposeDimensions();
           // Enforce minimum dimensions to prevent layout issues
           const cols = dims ? Math.max(dims.cols, MIN_COLS) : MIN_COLS;
@@ -3848,6 +3851,14 @@ Object.assign(CodemanApp.prototype, {
       return;
     }
 
+    // The pane belongs to the popup showing it, so this window has nothing to
+    // restore. Say so rather than reporting a size that was never sent — the
+    // same button in that window does the job.
+    if (!this.isSoloWindow && this.detachedSessions?.has(this.activeSessionId)) {
+      this.showToast('This session is sized by its own window', 'warning');
+      return;
+    }
+
     const dims = this.getTerminalDimensions();
     if (!dims) {
       this.showToast('Could not determine terminal size', 'error');
@@ -4900,6 +4911,17 @@ Object.assign(CodemanApp.prototype, {
     // Fit terminal to container before reading dimensions — ensures local
     // terminal size matches what we report to the server PTY.
     if (this.fitAddon) this.fitAddon.fit();
+    // One PTY cannot hold two sizes. A detached session is owned by its own
+    // window, and the dashboard's terminal is narrower than that window because
+    // the session rail takes width the popup does not have — so both sizing it
+    // makes the CLI draw frames that fit neither, which garbles the popup. The
+    // dashboard yields; the solo window sizes what it alone displays.
+    // (_maybeRefetchFullHistory already stands aside for the same reason.)
+    // ⚠️ AFTER the fit, never before: the local reflow keeps the dashboard's own
+    // xterm right, and only the SERVER write is the dashboard's to withhold —
+    // the mobile-keyboard guard below draws exactly this line. tab-rail-resize
+    // performs its one settle-time refit through this call and has no fallback.
+    if (!this.isSoloWindow && this.detachedSessions?.has(sessionId)) return false;
     const dims = this.getTerminalDimensions();
     if (!dims) return false;
     // Did the dimensions actually change since the last resize we sent? Callers