Firefox missing cursor in input fields

This is a known bug in Firefox, which has existed for quite some time. It is surprising that it is not fixed after so long. Some reports on Bugzilla say the bug is fixed, but obviously they are wrong.

Some of the reasons I have found for this anomaly are as follows:

1. animated gif was loaded with the page
   • FIX: remove the animated gif, such as a loading indicator from the document using javascript
2. input field is on top of a div with scrollbars, such as with overflow: auto
   • FIX: temporarily change overflow: auto to overflow: hidden, then change it back; this is common when a javascript dialog div is presented to a user