Clicking on "Watchers" number icon to add watchers is not giving an option to add watchers. Instead the list moved upwards and the "Add Watchers" option is cropped.
- Create an issue. (Make sure you have at least 40 users in your JIRA)
- Add all the users as "Watcher" for the issue.
- Click on the "Watchers" number icon to view all the watchers.
Problem is not browser related.
Use the More > Add Watchers option to add watchers to an issue.