Hi, I've been trying to explain this odd behaviour to Abine, but they seem to have lost interest. It may highlight another odd behaviour of FF I wasn't aware of. After a huge amount of head scratching and trial and error with Blur, I have established the following: Starting with a new FF profile, I can install the app 'Blur' from its web site. It has a blue toolbar button, and it works fine... Until I close FF and open it again. When I open it again, Blur is running--according to app manager--but there is no button, and no way to log in to Blur, without going on line to their site. If I do go to their site and log in: it tells me I need to install the extension even though it is already running. I then install the extension over the top, or after deleting the old one--makes no difference--and I *don't* get my button back! Only first time with a new profile. I had more or less given up, when I accidentally opened a new window when I went to open a new tab. The new window had a blue button! But it still didn't connect to anything. :/ Then I noticed that, when the button appeared in the second window, it also appeared in the first window! But wasn't connected to anything in either. :/ First time this happened, I closed the first window, and went through the reinstall process on the second one. Again, Abine's 'dashboard' still said I needed the app even though it was running and had the button. So, installed again, over the top, and this time, I had Blur fully operational in the second window. Thinking I had better save the profile settings and hoping they would carry forward the working Blur, I went to back up with FEBE... Then I discovered what I had never heard of: the first window, is 'the controlling window' *even if you just closed it*! FEBE insists on backing up from the 'controlling' window so I could not back up from the window I now had Blur working in! :/ And, of course, when I close it, and open, Blur is gone again. :( Anyhow: I am now using Blur (though, frankly, it is not as good as MaskMe was, and does not always fill in my passwords.). The way I have to proceed, is: Open FF; Open new window--*Not* closing first window; In second window: go to Abine and log in to your dashboard on their web page (you can't use the button for this: must use address bar); Once you log in, you are prompted to install the app, even though it is running according to app manager; Install the app despite the blue button that tells you it's already there; When you finish the install, you will see that the first 'controlling' window, now has a rotating blue button too; Shut the *second* window. You can now use Blur for as long as you like... Until you close FF... Then you go back to stage one and do it all again! ACTUALLY: Once you get used to the procedure it isn't too bad, and is a handy extra security feature, which nobody will ever crack! This is even more so, because Blur does not have the 'insist on log in at start' setting, that was on MaskMe. OK then: Who can tell me what on Earth is going on?! Why aren't all FF windows the same, for starters? p.s: I should probably note that the Blur button does not at any time appear in the customisation box, so you cannot drag it to the toolbar: it just installs in position, and stays there till you shut FF and open it again. It is then invisible in the controlling window, but still there in any further window you open. Oh: And one more thing I tried: When FF updated to 44, I thought I would try to be clever: I made a new profile for 44. Opened the old one in 43; went through the rigmarole above, to get it working with Blur. Then I backed up the working 43 profile, and restored it into the new 44. This time, when I hit the FF button and selected profile 44, a window opened that had a blue button from the start! Just as I was thinking I'd cracked it, *another window opened on its own*; which also had a button!! Then both windows shut, and there was no button, or spare window when I opened FF the next time. So it was back to square one. :/ :/ Confused? Yes indeed! But amused too. :) Many thanks for any explanation. If no explanation: then this might be needing a bug report. Cheers.