I do not see any attachments. however this might be your problem. (https://support.mozilla.org/en-US/questions/966712)

If you have the Ghostery extension installed, that is the most likely cause. Disable Ghostery in the Add-ons Manager it to verify it as the culprit.

Start Firefox in Safe Mode to check if one of the extensions (Firefox/Tools > Add-ons > Extensions) or if hardware acceleration is causing the problem.

• Switch to the DEFAULT theme: Firefox/Tools > Add-ons > Appearance
• Do NOT click the Reset button on the Safe Mode start window

• https://support.mozilla.org/kb/Safe+Mode
• https://support.mozilla.org/kb/Troubleshooting+extensions+and+themes