but then that's two different accounts to manage and the good SAML login stuff doesn't seem to be included. so 14 minutes to write a quick script to readd the button seemed easier
so the most likely cause is there's some sort of script blocker, either in your browser or on the network. Or, your browser is not allowing Javascript to run.
so this issue started to happen yesterday, after I had purchased Norton Anti virus because my pc started to have pop ups saying that my pc is at risk. @Ramstik
You have a virus on your computer that is causing this. Nothing you can really do except finding and deleting the virus, which can be tricky if it's already replaced core system files.
The antivirus itself is causing this, or you installed a fake antivirus that targets users by claiming that they have a virus in order to install itself. Either way uninstalling the antivirus might work.
Metamask is causing this, in which case disabling it will fix it.