> (Of course Fossil actively opposes "pull requests", separate issue)

Not opposition, but very little incentive for the primary developers to implement the feature. Fossil's own developers happen to be the same as SQLite's developers, which doesn't accept outside contribution as a policy. It results in Fossil's features being predominantly, but not exclusively, the same features needed for SQLite and little else.

This thread discusses avenues for implementation: https://fossil-scm.org/forum/forumpost/ce238fccfd6b124d