Accordion crashing on clicking some links

Hi there,

We're using moodle 3.1, and in Firefox and potentially IE on desktop, when we use the accordion, clicking some links within the text cause the accordion to 'crash'; the accordion disappears from the page. Not all links are affected, but it is consistent behaviour in terms of which links do and don't cause the crash.

We're embedding the content from h5p, although we re-created the error when using the content directly created in moodle and then using an iframe into a label. HOWEVER, when we access the module directly (as a resource type, not via an iframe), we don't experience the error. The links then do open, but they open in the same window, despite having specified them as 'target - new window'. Changing the links to 'target - same window' doesn't solve the issue in the iframes - the accordion still crashes.

On the Firefox browser console, the below shows when clicking on one of the links that cause the crash:

Security Error: Content at https://www.undergraduate.study.cam.ac.uk/fees-and-finance may not load data from https://vle.medschl.cam.ac.uk/course/view.php?id=662&sectionid=10837.

Load denied by X-Frame-Options: https://www.undergraduate.study.cam.ac.uk/fees-and-finance does not permit cross-origin framing.

Any ideas? Many thanks in advance for help!

Best,

Al