I use Firefox and open groups of many bookmarks: the PC can freeze! I have a workaround. Install Clear Cache add-on. You can also install Cache Toggle add-on.
https://addons.mozilla.org/en-US/firefo ... ent=search
https://addons.mozilla.org/en-US/firefo ... ent=search
Clear the cache.
Menu File click Work Offline.
Open the group of bookmarks.
Wait just seconds.
Menu File click again Work Offline to go online with Firefox and reload tab by tab your bookmarks.