Session recovery
Type into a new tab, quit without saving, and the tab is still there next time. That is the Notepad++ trick, and it is the one behaviour people miss most when they move to a Mac editor that treats every buffer as a file or nothing.
The mechanism
Two things are kept: a manifest describing each window, and the text of any buffer with unsaved work. They are separate because most tabs need only the first.
Which buffers were open, the ids in each pane in tab order, which tab was on top of each pane, and which pane was active. A buffer showing in two panes appears in both, so a split is restored as a split rather than as two copies.
Each window keeps its own manifest, so all of them come back in the order they were open, at the size and position they had. Closing a window forgets that window rather than the session.
A saved file with no edits records no backup — the disk is the truth for those, so reopening picks up whatever changed while the app was closed rather than restoring a stale copy over it.
“new 3” comes back as “new 3” rather than being renumbered, because the number is stored with the buffer and is also what Save As offers you.
A file you had reinterpreted as Shift-JIS is still Shift-JIS after the restart. The tab’s format is part of the snapshot, not something re-guessed on open.
Off the main thread, through one serial queue so writes land in order — and the queue is drained before the process exits, so a normal quit does not race the last keystroke.
Superseded backups are moved aside rather than deleted, into a folder that is swept after two weeks. Long enough that somebody who notices the next morning still has it; short enough that it is not an archive.
Specifics
The boundary matters more than the feature. Recovery here means Linelark’s snapshot of your session, and nothing wider than that.
| After a quit or a crash | Restored? |
|---|---|
| An untitled tab you never saved | Yes, with its text and its number. |
| Unsaved edits to a saved file | Yes, from the backup written as you typed. |
| Which files were open, and in which pane | Yes, including one buffer shown in two panes. |
| The pane layout and the active pane | Yes. |
| Every window that was open at quit | Yes, in order, at the size and position it had. |
| A terminal that was running | No. Shells are not saved with the session. |
| Each tab’s language, encoding and line endings | Yes. |
| A saved file with no unsaved edits | Reopened from disk, so external changes are picked up. |
| A file you closed before quitting | No. Closing a tab takes its backup with it. |
| A file you deleted in Finder | No. This is not a filesystem undo. |
Read from the Linelark Studio 1.19.0 source, not from its documentation. Where the two disagree, this is the one that ships.
Before you rely on it
Session recovery is easy to oversell into sounding like a backup system. It is not one, and the difference is worth being blunt about.
Free, and staying free
Apple-notarized, macOS 14 and newer, Intel and Apple silicon.
Download Studio 1.19.0 8.7 MB · every version, with checksums