Attachment added in the wrong issue

Problem Description

Attachment is added in the wrong issue when the uploading isn't complete and user clicks on a different issue.

Step to Reproduce

1. Have a board and 2 issues
2. Go to Backlog view
3. Click issue-1 until the Issue Details panel open
4. Attach big file attachment (ie. 9Mb)
5. While it's uploading, click the second issue and wait until the attachment is uploaded.

Actual Result

The attachment is added to the second issue.

Expected Result

The attachment is added to the first issue.