This might be good to know about: The new (much improved) Trac version (perhaps with some plugin or settings) surprised me again when it closed ticket automatically after putting “closes #…” or “fixes #…” into a commit message. It might be a good feature for us, except when backport, unittest, documentation or testing is needed.
See this for an example:
https://trac.osgeo.org/grass/ticket/2997#comment:4
https://trac.osgeo.org/grass/changeset/68396
https://trac.osgeo.org/grass/ticket/3026#comment:1
https://trac.osgeo.org/grass/changeset/68403
Best,
Vaclav