How to replicate:
1. Highlight any piece of text
2. In the menu that appears, click "Link"
3. In the panel that pops up, left-click any button or anything
4. The window will close regardless of what or where you click
Step 4 makes linking anything with this menu practically impossible. However the other menu, "Insert Link" from the bottom of the page, without highlight text, *doesn't* seem to have this problem.