fix: fit view — reapply layout on session close, show more lines, bottom-anchor content

Bug 1: closeSession() didn't call applyFitLayout when returning to
dashboard — tiles kept old heights from before the overview was hidden.
Fix: add rAF call after overview.style.display = '' so the layout is
remeasured once the overview becomes visible again.

Bug 2: Only 20 lines shown in tiles — not enough for tall fit-mode
tiles, and content sat at the top. Fix:
  - buildTileHTML shows 80 lines in fit mode (vs 20 in auto)
  - renderGrid rAF sets pre.scrollTop = pre.scrollHeight after
    applyFitLayout so content anchors at the bottom (like a real
    terminal). Hidden scrollbar via scrollbar-width:none + ::-webkit.

Tests: 3 new source-scan tests added and verified RED before GREEN.

muxplex/frontend/app.js

@@ -400,9 +400,11 @@ function buildTileHTML(session, index, mobile) {
     bellHtml = `<span class="tile-bell">${countStr}</span>`;
   }
 
-  // Last 20 lines of snapshot
+  // Last N lines of snapshot — show more in fit mode so tall tiles fill
   const snapshot = session.snapshot || '';
-  const lastLines = snapshot.split('\n').slice(-20).join('\n');
+  var _tileDs = loadDisplaySettings();
+  var _lineCount = (_tileDs.viewMode === 'fit') ? -80 : -20;
+  const lastLines = snapshot.split('\n').slice(_lineCount).join('\n');
 
   return (
     `<article class="${classes}" data-session="${escapedName}" tabindex="0" role="listitem" aria-label="${escapedName}">` +
@@ -652,7 +654,13 @@ function renderGrid(sessions) {
   var currentMode = currentDs.viewMode || 'auto';
   if (currentMode === 'fit' && grid) {
     grid.classList.add('session-grid--fit');
-    requestAnimationFrame(function() { applyFitLayout(grid); });
+    requestAnimationFrame(function() {
+      applyFitLayout(grid);
+      // Scroll each tile's pre to the bottom so content anchors at the bottom (like a real terminal)
+      grid.querySelectorAll('.tile-body pre').forEach(function(pre) {
+        pre.scrollTop = pre.scrollHeight;
+      });
+    });
   }
 
 }
@@ -1003,6 +1011,16 @@ function closeSession() {
   }
   if (overview) overview.style.display = '';  // overview uses view--active (no !important), style.display clears fine
 
+  // Reapply fit layout after overview becomes visible again
+  var _closDs = loadDisplaySettings();
+  if ((_closDs.viewMode || 'auto') === 'fit') {
+    var _closGrid = document.getElementById('session-grid');
+    if (_closGrid) {
+      _closGrid.classList.add('session-grid--fit');
+      requestAnimationFrame(function() { applyFitLayout(_closGrid); });
+    }
+  }
+
   const pill = $('session-pill');
   if (pill) pill.classList.add('hidden');
 

muxplex/frontend/style.css

@@ -1380,10 +1380,16 @@ body {
   overflow: hidden;
 }
 
-/* In fit mode, stretch pre to fill the full tile body height (not just bottom-anchor) */
+/* In fit mode, stretch pre to fill the full tile body height and anchor content to bottom */
 .session-grid--fit .tile-body pre {
-  top: 0;           /* stretch to fill full tile body height in fit mode */
+  top: 0;                   /* stretch to fill full tile body height in fit mode */
-  overflow-y: auto; /* scroll if content exceeds the tile */
+  overflow-y: scroll;       /* enable scrollTop positioning (content anchored via JS scrollTop=scrollHeight) */
+  scrollbar-width: none;    /* Firefox: hide scrollbar */
+  -ms-overflow-style: none; /* IE/Edge: hide scrollbar */
+}
+
+.session-grid--fit .tile-body pre::-webkit-scrollbar {
+  display: none;            /* Chrome/Safari: hide scrollbar */
 }
 
 /* ============================================================

muxplex/frontend/tests/test_app.mjs

@@ -2212,3 +2212,32 @@ test('applyFitLayout is called via requestAnimationFrame for correct timing', ()
     'applyFitLayout must be deferred via requestAnimationFrame'
   );
 });
+
+// --- Fit view bug fixes: closeSession reapply, more lines, bottom-anchor ---
+
+test('closeSession reapplies fit layout when returning to dashboard', () => {
+  const source = fs.readFileSync(new URL('../app.js', import.meta.url), 'utf8');
+  const fnStart = source.indexOf('function closeSession');
+  assert.ok(fnStart !== -1, 'closeSession function must exist');
+  const fnBody = source.substring(fnStart, fnStart + 1500);
+  assert.ok(
+    fnBody.includes('applyFitLayout'),
+    'closeSession must call applyFitLayout for fit mode when returning to dashboard'
+  );
+});
+
+test('buildTileHTML shows up to 80 lines in fit mode', () => {
+  const source = fs.readFileSync(new URL('../app.js', import.meta.url), 'utf8');
+  assert.ok(
+    source.includes('-80') || source.includes('(-80)'),
+    'app.js must use -80 slice for fit mode to show up to 80 lines'
+  );
+});
+
+test('CSS style.css has scrollbar-width none for fit mode pre to hide scrollbar', () => {
+  const source = fs.readFileSync(new URL('../style.css', import.meta.url), 'utf8');
+  assert.ok(
+    source.includes('scrollbar-width: none'),
+    'style.css must have scrollbar-width: none for hidden scrollbar in fit mode pre'
+  );
+});