disable it in installer
How exactly? I see only one item relating to Explorer in the custom installation options. Even if I disable that the installer still shows a popup about closing Firefox.
BTW I’ve seen that popup for years every time I update LO and it is always and only Firefox that the installer wants to close. I also use Chrome and other programs with File Open/Save dialogs. So there seems to be something special to the combination of Firefox and LibreOffice.
In one case, it might be OK to ignore, in others not.
The popup should then say that. Perhaps something like “Might in some cases be necessary” to close Firefox (or whatever process) and/or restart the PC. Rather than “required” period.