Extended attribute data disappears

I have an installation of COmanage 1.0.6 with a MySQL database backend on Scientific Linux 7 and am having trouble with extended attribute data disappearing. Reproduce with these steps beginning with no extended attributes:

1. add an integer extended attribute
2. select your CO person and a role, save "100" in the attribute.
3. exit and re-enter the role, the value is still there.
4. add a second integer attribute
5. select your CO person and role, save "100" in the second attribute.
6. exit and re-enter the role, the second value is not there.

The problem seems to go away when debug level is set to 2 in app/Config/core.php.

We saw the same problem on https://registry-beta.cilogon.org/registry but the testing wasn't as rigorous there.