At first, this issue was used to report two issues, one of which was fixed elsewere. The remaining issue is:

1. Go to a question bank.
2. Create a question with a tag.
3. In the question list, click on the Badge that shows the tag name.

Actual result: As is normal for clicking on a tag anywhere in Moodle, you get taken to the page that lists all uses of that tag ... except that that page does not include questions. See MDL-59781.

Expected result: ... It's not really clear.

Original report:

Just tested on the QA site. Got the error below after doing the following (as an editing teacher):

1. Open Quiz > Questions (in my case this was https://qa.moodledemo.net/mod/quiz/view.php?id=1171)
2. Add question from question bank
3. Add some filtering possibly, e.g. by some tags
4. See questions listed with various coloured tags
5. Click on a coloured tag displayed with a listed question - the idea being - perhaps clicking on the tag will auto-filter the all the questions marked with this tag?
6. None of what I expected in 5 happened, After having done the above, I can see:

Must provide a cmid or courseid

error/Must provide a cmid or courseid
File: /question/editlib.php
Line: 248
Stack trace:
Error code: Must provide a cmid or courseid
$a contents:

• line 248 of /question/editlib.php: core\exception\moodle_exception thrown
• line 2512 of /mod/quiz/lib.php: call to question_build_edit_resources()
• line 2337 of /mod/quiz/lib.php: call to build_required_parameters_for_custom_view()
• line ? of unknownfile: call to mod_quiz_output_fragment_quiz_question_bank()
• line 7465 of /lib/moodlelib.php: call to call_user_func_array()
• line 415 of /lib/external/externallib.php: call to component_callback()
• line ? of unknownfile: call to core_external::get_fragment()
• line 253 of /lib/external/classes/external_api.php: call to call_user_func_array()
• line 83 of /lib/ajax/service.php: call to core_external\external_api::call_external_function()

Possible solution: Maybe the tag labels / pills shown for questions in the add questions modal should NOT be clickable?

Have not tested other Moodle versions, only the current QA site.