The panel won't open
Nothing happens on Alt+T, or the side panel is blank.
Why: Another extension has claimed the same shortcut, or Chrome never assigned it.
Fix: Open chrome://extensions/shortcuts, find Tabruns, and set the shortcut yourself. Clicking the toolbar mark always works regardless.
Why: It is unpinned, behind Chrome's puzzle-piece button.
Fix: Click the puzzle piece, then the pin beside Tabruns.
Why: The panel's own page failed to load, usually after an update that replaced the extension underneath an open panel.
Fix: Close the panel and reopen it. If it persists, reload the extension at chrome://extensions.
Why: Chrome does not let any extension read chrome:// pages, the Web Store, or other extensions' pages. This is a browser rule, not a Tabruns setting.
Fix: Switch to an ordinary website. There is no permission that unlocks these.