Skip to content
Molkit

Tabs, Auto-Save & Recovery

Molkit holds several open documents at once, one per tab. Every tab is an independent document with its own canvas, undo history, and settings. While you work, Molkit writes all open tabs to your browser’s local storage on a short timer, so a closed or crashed tab can be restored the next time you open the app. This saving is per browser and per device; it does not sync and it is not a substitute for saving a .mkit file to disk.

Tabs

The tab bar sits below the toolbar. Each tab shows its filename and a dot when it has unsaved changes. New documents are named Untitled 1, Untitled 2, and so on, reusing the lowest free number.

Opening, closing, and switching

  • Click the + button at the end of the tab bar, or press Ctrl+T, to open a new blank tab.
  • Click a tab to switch to it. Ctrl+Tab moves to the next tab and Ctrl+Shift+Tab moves to the previous one. Ctrl+1 through Ctrl+9 jump straight to a tab by position.
  • Click the close (x) button on a tab, or middle-click the tab, to close it. If the tab has unsaved changes you are asked to Save, Don’t Save, or Cancel first.
  • Drag a tab left or right to reorder it. Scroll the wheel over the tab bar to scroll through a long row of tabs.

Molkit always keeps at least one tab open, so closing the last tab opens a fresh blank one. Ctrl+W is left to the browser and does not close a Molkit tab.

Tab right-click menu

Right-click a tab for these actions:

  • Close Tab
  • Close Other Tabs (keeps only the clicked tab)
  • Close Tabs to the Right
  • Duplicate Tab (opens a copy of the document in a new tab, marked unsaved)
  • Close All Tabs (closes everything and opens one blank tab)

Closing a group of tabs that contains unsaved changes asks for confirmation first.

Tab gestures are blocked while a dialog is open. Close the dialog before switching, creating, or closing tabs.

Auto-save

Auto-save records every open tab to your browser’s local storage under a single key. A save runs about two seconds after your last change, and a full force-save also runs every 30 seconds as a safety net. Selection, panning, and zooming do not trigger a save, and saves are skipped during a continuous drag.

Auto-save runs in the background, so it does not interrupt an in-progress text edit. Text you have typed but not yet committed is captured on the next save after you commit the edit by clicking away or pressing Esc.

Local storage has a size cap, so Molkit prunes data as it approaches roughly 4.5 MB:

  1. Trim each tab’s undo history to the last few entries and drop redo history.
  2. Drop undo and redo history for all tabs. A status-bar warning appears.
  3. Keep only the active tab’s full content, with other tabs reduced to metadata. A stronger warning tells you to save your work manually.

If the browser still refuses the write (quota exceeded), Molkit falls back to saving only the active tab. When this happens, save a .mkit file to disk so nothing is lost.

Recovery

When you reopen Molkit, it checks local storage for a previous session and restores your tabs if any of them had content, a real filename, or unsaved changes. Your previously active tab is selected.

On Firefox and Zen, Molkit also keeps a copy of the current document in the browser’s Origin Private File System (OPFS) for session recovery. This runs only when local-storage recovery did not already restore your work: it is skipped if more than one tab is open, if a tab with the same filename exists, or if the active tab already has content. On Chrome and Edge, Molkit uses real file handles instead, so OPFS recovery does not apply there.

Recovery restores what was in browser storage at the last save. For long-term storage, sharing, or moving between devices, save a .mkit file.

See also