Unfortunately this is due to a browser bug. :(
You might notice this if you have entered a long task name, and after the name have added a tag (or another property) via the auto-suggest.
The cursor may look like it's disappeared, however using the arrow keys to move to the end of the input field will reveal the cursor.
This issue only affects some browsers, which do not correctly scroll the field to the right to the new cursor position.
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