I have this item on a page <a role="option" href="[looong url]">My Item</a>
After clicking on this item in Firefox in regular mode NVDA reads:
document busy
[looong url from browser's address bar]
application
My Item
When I click on the item again it doesn't read the url (desired behavior):
document busy
blank
application
My Item
In the meantime when I do the same thing in Firefox in private mode it reads every time as expected:
document busy
blank
application
My Item
Is that an expected difference in FF behavior for regular and private modes?
As per NVDA developers forum it is a Firefox issue related to browser's inconsistency in private and regular mode while reading the same page by a screen-reader.
https://github.com/nvaccess/nvda/issues/6573
Thus the question might be closed.