The issue has been fixed now!
Guys, we deeply regret the inconvenience caused to you with an understanding of the situation there with you where every time you have to see the flash of Enpass helper (as extension window). But truly speaking this was a very nasty bug hidden behind the layers of OS causing the extension to go out of scope if the browser was started after the Enpass. And while in process of fixing this issue we were in such an unsettling situation that we were not able to update you with any expected ETA.
Well, this weekend we made ourselves to resolve this issue, and finally, it has been squashed now. The fix will be available to you in the upcoming beta version very soon. You can get the updates for beta versions here in the Forums: https://discussion.enpass.io/index.php?/topic/1161-enpass-beta-v55-for-desktops-brings-attachments-support/
Thanks for your understanding and co-operation.