Page Zoom is broken for me now in Version 16.3 (18614.4.6.1.5) on Ventura 13.2 (22D49) It goes like this: 1. Open any website 2. Start zooming in any way — via hotkeys or the View ➜ Zoom menu 3. The zoom is updated in the same second 4. After about 2-3 seconds, the zoom returns to 100% value. But it's not always 100% — sometimes I open a site that's already zoomed out or in, and if I hit cmd+0 to Zoom to 100%, the same thing happens - after a second or two, the zoom snaps back to what it was. My "Fix" is to zoom the page to 100% and then quit Safari before it snaps back. Then the page seems to have "learned" the new setting. This does not seem to happen in Safari Technology Preview Release 162 (Safari 16.4, WebKit 18615.1.18.2) and neither in Release 163 (Safari 16.4, WebKit 18615.1.18.100.1)
<rdar://problem/105196766>
I can reproduce this right here in Bugzilla (same Safari and macOS version).
This turned out to be a Safari issue, only happening when Safari Technology Preview is also installed (just installed, does not have to be launched). Marking Invalid, as this will need to be fixed outside WebKit. I am not aware of a workaround.