You can quickly and easily bulk-tag related documents from the document viewer:
Tag/Untag Dupes - bulk tags the document in the viewer + related duplicates.
Tag/Untag Families - bulk tags the document in the viewer + related families.
Tag/Untag Threads - bulk tags the document in the viewer + related threads.
Click to open the tag drawer from the tools on the right, then hover over the vertical dots to view tagging options and choose from the list.
