Some issue menu's sub-items are not accessible and are not readable when using screen readers

Issue Summary

When browsing Jira, not all sub-menus are accessible using keyboard, and thus are not readable by the screen readers.

Environment

• Jira 7.6.11, 7.13.1, or some of the earlier versions
• Any modern browser (tested on Edge, Firefox and Chrome)
• NVDA 2018.4.1 (but will also be reproducible with older versions, as it's an issue with Jira's navigation, not with the screen reader)

Steps to Reproduce

1. Head to the issue.
2. Press 'H' until you reach the Summary heading.
3. Using the 'K' button on the keyboard, head to the next link until you reach the 'More' button. Enter Focus Mode by pressing NVDA+Space. (NVDA is the insert button by default)
4. Press 'Enter', then navigate to the sub-menu using the keyboard.
5. You are unable to navigate the submenu properly using just the arrow keys - the furthest you can go is until the "Attach files" item.

Expected Results

All menu items will be accessible and readable by the screen reader.

Actual Results

Not all menu items are accessible using just the arrow keys.

Workaround

One has to jump to the end of the virtual buffer to access the menu items after "Attach files".
Those items will be accessible by keyboard, but will not be read properly.