Further note sent to #1Password support.
Hi,

I’ve been able to reproduce the “mark” announcement issue outside of 1Password using a minimal HTML test case.

Specifically:
When text is wrapped in either a `<mark>` element or an element with `role="mark"`
And presented in a read-only “viewer”-style container
JAWS announces “mark” and “end mark” during line-by-line navigation

This suggests that in 1Password:
The Secure Notes viewer is intermittently exposing “mark” semantics
Likely due to unintended or stale highlighting (I also observe occasional colour changes)

Since this occurs even when:
Markdown is disabled
The note contains only plain text

It appears that the issue is not content-related, but rather due to how the viewer component renders or updates its accessibility tree.

I have written code to simulate this at
https://hartgenconsultancy.com/test