This looks like the matrix-auth plugin is disabled or unable to load. Check
the Jenkins log with the error message for why that is.
1.5 is really old, you should update -- probably before the next attempt at
updating Jenkins. It's almost certainly safe to do so, this is the
documentation underlyin
Last week, I tried to update to Jenkins 2.235.1, but Jenkins would not
come up; it was an error about ProjectMatrixAuthorizationStrategy (see
error stack at bottom of email).
Moving back 2.164.1 war did not work, I had to use snapshot of VM to
recover. Now, I'm wondering what the best path for
