[0.1.0]

The first numbered version. It does not try to describe everything preen does; the README does that. It records the work that landed before versioning began: mostly names and paths that preen listed wrong or could not open, and the CI that now runs on the platform preen is most used on.

Added

preen --version says which preen this is (-V, or preen version). It reads the VERSION file at the root of the checkout preen was run from, which it finds by resolving the symlink install.sh puts on your PATH. A checkout whose VERSION cannot be read answers preen unknown and still exits 0: the version is what you ask for when something is wrong, so it is the one question that must not fail.
CI runs the test suite on macOS as well as Linux (#23, PR #26). macOS ships bash 3.2 and BSD sort, find and awk, and the file lists are built from exactly the constructs where those disagree with bash 5 and GNU. The macOS job is pinned to the system bash, so a newer one on the runner cannot quietly take the 3.2 coverage away. Tried against 16 constructs that break on 3.2 or BSD, the macOS job failed on all 16 and the Linux job on none.
CI runs site/sync-assets.sh instead of only parsing it (#27, PR #29). A --dry-run resolves every source and destination without encoding anything, and the workflow compares the destinations with the five images the site actually reads. A renamed tape or a mistyped output name now fails CI; before, it shipped green and left the old image in place. A third runner OS added to the matrix now stops with a message naming it, not deep inside the suite.
Every GitHub Action is pinned to a commit (#28, PR #29), with its version in a comment and Dependabot keeping both current. A tag can be moved to other code; a commit cannot. The workflow also states permissions: contents: read instead of inheriting the repository default, which took away a packages: read nothing used.

Fixed

A filename with a quote, a backslash or a newline is listed and opens (#3, PR #19). git escapes those bytes whatever core.quotePath says, so the name was listed in a spelling nothing could open, and the preview was blank. A newline was worse: it also split one file into two entries, so a worktree's count was too high. Every list is now read on NUL, the one byte a filename cannot hold, and fzf is told to read it that way.
pr mode previews an accented or odd name (PR #19). git quotes the whole path in a diff --git header when the name holds a quote, a backslash, a control character or any byte above ASCII, so every accented name arrived quoted and the preview matched nothing. preen decodes the header now.
A tab in a worktree's directory name no longer breaks worktrees mode (#24, PR #31). The record joined its label and its path with a tab, and the label already ended with the path, so the split landed in the wrong place. The pane counted two files, showed a blank preview, and then said the branch had changed nothing. The two fields are joined on a byte no real name uses.
A worktree preen cannot open is explained honestly (#25, PR #31). A worktree deleted by hand without git worktree prune was blamed on git being older than 2.36, on any git, and preen exited 1 if it was the only one. Now the advice is to prune if it is gone for good, and git's version is named only when git really is too old. On that older git, a newline in a worktree's name used to list a plausible worktree that did not exist; that entry is dropped now, and the picker's header says one went.
preen md on a directory whose name starts with a dash finds its files (#22, PR #31). find read the name as options.
pr mode no longer previews two files stitched together (#22, PR #31). A PR holding x.md and a file named b/x.md matched both when previewing x.md. The header is now split exactly instead of matched on its tail.
The mouse wheel scrolls a rendered file (#36, PR #37). preen FILE.md and piped input page through less, which was never asked for the mouse, so under tmux the wheel did nothing while every picker mode scrolled. less is given --mouse when it supports it. The cost: a plain drag now selects inside less, so copying a line wants tmux copy mode or a modifier key, and the docs now say so (PR #39).
A narrow pane no longer folds a render twice (PR #41). preen asked tput for the width in a way that often answered 80 whatever the pane was, so in a 66-column pane a piped render was 80 wide and less wrapped every line again, mid-word. preen now asks the terminal itself. COLUMNS still wins, and 80 is still the answer when there is no terminal at all.
The site stopped serving its build manifest (#7, PR #30). /nitro.json was public with a week-long cache, for a file that changes on every deploy and that nothing reads. It is left out of the image now.
An image the site cannot size fails the build (#5, PR #30). The site reads sizes from PNG and WebP headers only. Anything else reserved no space on the page, so the layout shifted as it loaded, and nothing said so. The build now stops and names every such image. Converting it to WebP, or writing the tag with both width and height, is the way out.

Known limits

pr mode cannot list a filename that contains a newline. gh pr diff --name-only separates its output with newlines and has no NUL form, so such a name cannot be told apart from two. Every other odd name lists and opens in pr mode.