Suggestion: filtering on more than one tag

[PatrickHonorez]

Perhaps I missed something but it does not seem feasible.
An idea: long press on a tag in the menu would add that 'filter' to the current one.

[1nsp1r3rnzt]

That makes sense.

Also, for users with a lot of tags, upon selection of a tag, an option to show only sub tags would be beneficial.

Another option can be to add an icon to filter according to tags in the Toolbar near search button.

UseCase:
Suppose a user is viewing Tag A. The results are

Bookmark a
Tag A, Tag B, Tagc

Bookmark b
Tag A, Tag D, Tag E

Bookmark c
Tag A, Tag C, Tag B, Tag E

Now, when the user clicks the filter icon, it opens a popup
The tags can be sorted according to frequency, then sorted by name
The options would be
[+] Tag A (indicating current selected tag)
[] Tag B (next most frequent tag with Tag A)
[] Tag C (so on)