My troubleshooting steps:
I uninstalled Security Assist, which is the only extension that had been updated before issues began.
I uninstalled HTML Ed 3.
I deleted all WA files/folders from domain with the problem.
I deleted the .dat file.
I reinstalled HTML Ed3.
Redid the Webassist page, redid the HTMLEd3 content area.
No change in Safari, Firefox (Mac) or on IE 9.
What else can I try?