I posted here, but the responses I got (although maybe well-intentioned) were TBH, very clueless. I'm hoping users in this MS Tech Community forum, might be able to offer an actual fix - or at least a decent workaround.
More recently, it's even started doing it with the personal (non-work) profile, it seems to have coincided (could be wrong) with having web apps installed, or at least quite a few more, for that profile.
Quite fond of the stable branch of edge chromium but if this continues, I think I'm going to need to shift elsewhere. Too busy now, but in the next few months, it'll become more & more pressing.