Mozilla released two updates for Firefox 48, versions 48.0.1 and version 48.0.2 to be precise, hoping that they would fix the Websense compatibility issue in the browser.
In the meanwhile, it blocked updates for all users on Firefox 47.x and earlier to Firefox 48, and released a hotfix add-on to enable updates for systems without Websense.
Websense is a web filter and security solution for the Enterprise that offers monitoring, protection and management features in one package.
Firefox 49.0.1 released
The Firefox 49.0.1 release notes list only one fixed issue. It should not come as a surprise that the only issue that is mitigated is a startup crash issue caused by Websense on Windows devices.
Mitigate a startup crash issue caused by Websense (Windows only)
Mitigation means that the issue is not fixed. If you look up the linked bug report on Bugzilla @ Mozilla, you will realize that Mozilla has no solution for the issue yet.
Without a ton of information to go on, we’re going to put the shim back into place for windows users for 49.0.1. We will also keep the 48.0.x users who we *know* have websense, on 48 for now.
So, basically, what happened is the following: Mozilla pushed a fix to Firefox 48.0.2 that it hoped would fix the issue. Initial reports were fine, and the organization decided to remove the fix — using fake dlls — from Firefox 49.0 during release.
It then realized that Firefox installations on Windows were crashing left and right if Websense was installed on the system.
The organization decided then to release Firefox 49.0.1 to bring back the solution that it used in Firefox 48.0.2. It hopes that this will reduce the frequency of crashes and the number of crash reports that it receives in regards to Websense and Firefox.
Sorry about doing the hokey pokey here. We don’t have a good solution, but this may mitigate the frequency of the crash for websense users, so we are going to try it (again).
Also, it decided to block users on Firefox 48.x with Websense installed on their machines from upgrading to Firefox 49.x.
Firefox users who are held back on Windows from installing the latest version — regardless of whether they have Websense running on their system or not — may update manually to the latest browser version.
Simply download Firefox from Mozilla and run the installer once it has been downloaded to the local system.