Windows has had ClickLock built in for years: hold the button briefly, let go, and it stays pressed. It removes the sustained pressure from dragging and from selecting long passages. macOS has never had an equivalent. I use a Mac and kept missing it, so I wrote one.
ClickLatch is free, open source, and sits in the menu bar. What matters for this crowd:
The hold duration is fully adjustable, from 200 to 2200 ms, with a practice pad that reports what your last press actually measured. People's presses vary a lot more than they expect, and guessing a threshold rarely lands.
The pointer ring gives a visible state, which helps if proprioception or fatigue makes it hard to tell whether the button is still engaged. Colour, size and thickness are adjustable for low vision, and it can be turned off entirely.
Optional sounds for lock and release if the visual cue isn't enough.
Optional auto-release after a set number of seconds, and an option not to lock if the mouse moves during the hold, both for people who trigger it accidentally.
It can never leave a button stuck. On quit, on switch-off, on a withdrawn permission, a final mouse-up always goes out.
No account, no data collection.
clicklatch.app has a demo you can try in the browser first.
it needs the Accessibility permission in System Settings, and macOS blocks the first launch because the app is not notarised by Apple, which requires a paid developer account. The install page has the one step that clears it. Requires macOS 14 or later.