It's odd that your Firefox identified itself as version 46.

Please try updating: Update Firefox to the latest release

If your Firefox thinks it is up-to-date, check this article to see whether it explains why your version is reported inaccurately: How to reset the default user agent on Firefox

Note that you may need to update more than once to reach the current release (80.0.1, but 81.0 is scheduled for release next Tuesday). Best is to update via "Help -> About Firefox" to ensure migration code is run properly and prevent losing profile data that will likely happen if you install the current release directly.