I cannot reproduce this bug in an up-to-date Disco.
OK, I think I discovered something, when I updated mutter in bionic-proposed, it didn't pull the updated version of libmutter-2-0 and gir1.2-mutter-2. So I had a mix of:
mutter 3.28.3+git20190124-0ubuntu18.04.1
mutter-common 3.28.3+git20190124-0ubuntu18.04.1
gir1.2-mutter-2 3.28.3-2~ubuntu18.04.2
libmutter-2-0 3.28.3-2~ubuntu18.04.2
Now I cannot reproduce this bug after I manually installed libmutter-2-0 and gir1.2-mutter-2 from bionic-proposed.
So I think the problem is mixing old and new versions of mutter packages. This bug could be closed unless there is a need not to.
I cannot reproduce this bug in an up-to-date Disco.
OK, I think I discovered something, when I updated mutter in bionic-proposed, it didn't pull the updated version of libmutter-2-0 and gir1.2-mutter-2. So I had a mix of: git20190124- 0ubuntu18. 04.1 git20190124- 0ubuntu18. 04.1 2~ubuntu18. 04.2 2~ubuntu18. 04.2
mutter 3.28.3+
mutter-common 3.28.3+
gir1.2-mutter-2 3.28.3-
libmutter-2-0 3.28.3-
Now I cannot reproduce this bug after I manually installed libmutter-2-0 and gir1.2-mutter-2 from bionic-proposed.
So I think the problem is mixing old and new versions of mutter packages. This bug could be closed unless there is a need not to.
Thanks everyone.