So i do not know if there is a work around or i should
$ pamac upgrade ungoogled-chromium
Nothing to do.
$ sudo pamac install chromium
To install (1):
chromium 87.0.4280.88-2 extra 68,7 MB
To remove (1):
ungoogled-chromium 86.0.4240.198-1 (Conflicts With: chromium)
(ungoogled chromium is package from AUR) and then hope my browser configuration will be preserved (config files seems to be in ~/.config/chromium/) . When i last time tried to build it, it took half a day and was not complete yet, so i would not want to build it again as i consider it waste of PC resources.