Steps to reproduce:
This just happened randomly many weeks into working in a profile, so I have no idea.
I think shortly before this happened I downloaded a PDF from Google and it caused an infinite redirect loop, maybe related. Since then it happened again without an infinite download redirect loop, just by closing some tab in a big hieararchy. I find it happens after a while of working in a profile. Closing and re-opening profile window seems to help.
Note that the tab containing nested hierarchy cannot be closed (on the screenshot it’s the one labeled with json-ld), and cannot be switched to.
Update: there is a bug with repro that causes a similar GUI glitch, with non-nested tabs: https://orionfeedback.org/d/4380-malfunctioning-vertical-tabs-when-nesting-disabled (that repro doesn’t work for this bug though).
Orion, OS version; hardware type:
Version 0.99.123-beta (WebKit 6188.8.131.52) macOS Ventura 13.2 build 22D49