Add icon to activate Firefox signin rather than an automatic pop-up box

Is it possible to add an icon to activate the firefox login dialogue box for password access on desktop rather than having it appear automatically? The pop-up appears automatically and I constantly find I am typing something say in a search engine , only for the box to appear and half my text to be entered into the box. Also when I have already entered a password for a site, the box pops up again and I have to click cancel 2 or 3 times.

Which dialog is it – the “Master Password” dialog? Usually you’d only need to dismiss that once, unless a page is loading from a site for which you’ve saved a login. That might trigger it again. And after you enter it during your session, you shouldn’t be prompted for it again.

Yes, it’s the master password box. Whether I have saved a login or not, I would prefer to be able to make the decision as to whether I open the firefox password manager or use my own. Its doesnt only happen on on sites where I have to sign in. It happens all the time on startpage where I am typing into the search box, whic is not looking for a password.
So it seems that this pop-up appears whever a user input field is clicked into, which is too much of a generalisation. that’s why I think the option should be available to activate it myself rather than FF trying to decide when it should appear

Im using Linux, btw. Normally Arch or Manjaro

No, it shouldn’t fire for forms on sites where you don’t have a saved login.

If you have Sync configured, Firefox will want you to unlock the login for Sync purposes shortly after startup. Not sure whether that will keep happening at intervals.

I have been trying various things for the process of elimination and it does seem that its trying to login for sync purposes. But if I cancel the login and go to account/sync later, I have to enter the password there. This is more what I would like as default - only try to sync when I ask to, not flash pop-ups that I havent requested.
Similarly, I would prefer to go to account/passwords if I want to sign in somewhere using firefox, rather than having an automatic pop-up. I might not want to sign into a site every time I visit it.

For now, the best option I have is to sign out of FF to prevent the pop-ups. When I do this, however then in order to access passwords saved in FF, I have to sign in and then enter the same password again anyway.

So I suppose my feature request would be to be able to disable automatic sync requests and use the menu whenever I require a sync or access to passwords.