Favored notices/posts from specific sources don't show up in my list of favorites

Favored ("favorated"?) notices/posts from specific sources don't show up in my list of favorites. This happens regardless of the favorite is given from pleroma-fe, mastodon-fe or tusky. In the timeline the post will show up favored, but it won't show in my favorites (again in pleroma-fe, mastodon-fe or tusky). This happens only with posts from specific sources, that seem to be bots. But posts from other bots do show up in my favourtes when I favourite it.

• Source that fail: @Calvinn_Hobbes@tooot.im, @archillect@high.cat,
• Sources that work fine (in this regards): @aljazeera_english@newsbots.eu, @nos@newsbots.eu, @decorrespondent@newsbots.eu (hey, I see a pattern here...), pleromafeed@pleroma.site

I use the "favorite" method as a sort of bookmark, to later be able to find posts that I find usefull to remember. I did see the bookmark option in the Mastodon frontend. I am not aware if this feature will also land in the Pleroma-fe (that I favor)