I'm sorry to hear that you and your customers are experiencing constant tab crashes in Firefox. Let's try a few more troubleshooting steps to help resolve this issue. Since you've already done a clean install, refreshed Firefox, and disabled extensions, let's focus on some other potential causes. Firstly, try updating your graphics drivers and see if that helps. Also, check if there are any conflicting software or security programs that might be causing conflicts with Firefox. Additionally, you could try running Firefox in Safe Mode to see if the issue persists. If none of these steps work, it might be helpful to report the issue to Mozilla directly, so they can investigate further and provide more tailored assistance. Hope this helps, and feel free to reach out if you need more help!