Clicking to display attached files when creating a ticket sometimes gives access to random files that are attached to the opened bug report.
Steps
Select a bug report with attachements
Create a new bug report
Attach a file
Click on the "Attachement" button
The files of the bug report appear
Thanks for the report! This is Jira behaviour, please refer to https://aka.ms/MCBugTrackerHelp. Mojang does not manage the bug tracker base design/functionality itself.
Closing as invalid.