Symptoms

Mostly after performing a JIRA upgrade, the task board drag & drop feature stops working. For instance, you try to move an issue from To do to In Progress, and see the JavaScript loading icon starting to spin. This is an expected behaviour for sure, but the problem is that it keeps spinning endlessly though. There's no message written in JIRA logs.

Cause

When you move a card from one column to another every necessary action is performed by a JavaScript code. There was something breaking this script execution making it looping. Mostly, the culprit is an invalid character in the name of a specific resolution.

Resolution

Go to Administration > Issue > Resolution and verify the name of all resolutions you set. If there's one using double quotes (") replace it by a single quote (') and restart your instance.

There's the possibility of having another invalid char causing the issue. If so, in case you don't find the double quotes, look for any strange char and remove it from the resolution name.