When user accidentally submits string with trailing ","  -  for example "," or "abc," -  to the filter in the UI,  UI shows "This page is temporarily unavailable" message.

I understand this is due to the API 400 returned from API, but I believe UI could handle this edge cases somehow (e.g., by stripping trailing "," or at least with a message about incorrect parameter set and advice what to do to get rid of it. The general advice currently visible on the page is:

Try refreshing the page. If the problem persists, contact your organization administrator or visit our status page for known outages. 

which won't help in this case and thus user may get confused. But I believe the best would be to prevent these cases.

Steps to reproduce:

stage beta, cost-demo user

1. navigate to OCP details page
2. type "abc-" to "Filter by project" field and press enter

You will see "This page is temporarily unavailable" warning which won't go away even after recommended page refresh. You have to switch to a different page to get rid of the applied filter.