I cannot help you with those items. I used PureBrowser until Mozilla stopped supporting the old extensions–I liked TabMixPlus–in ESR 60.1. Additionally, the Purism webext packages seemed to interfere with my Quantum add-ons and, at the time, were down-level. I uninstalled it.
I am not sure if you mean add-ons, rather than ‘updates or certain app’. For add-ons, try what I wrote elsewhere in this forum. It helped a few people.
@mladen has also suggested this compat fix. It did not work for me with add-ons, but it might help you. Also, this made life easier for some other folks accessing sites, etc. For some reason, those sites are looking for ‘Firefox’ in the uagent string rather than ‘Gecko’.