Google released a new version of the Chrome web browser today. Version 76 includes a major surprise for those of us who still use web conferencing products that rely on Flash. The default setting now blocks Flash in the browser.
The official end of support for Flash is December 2020, so changing the default security setting without prior warning was unexpected at this time. Most web conferencing vendors have transitioned to HTML5/WebRTC browser support, but some still have a reliance on Flash. Two examples that spring to mind are Adobe Connect (for some presenter and host operations) and Webinato (for presenters, attendees, and on-demand viewers).
Users can still download and install Adobe Flash Player for use in other browsers, but Chrome had been particularly convenient since it bundled Flash internally and required no installation or updates by end users.
Changing the setting back to allow the use of Flash in Chrome is pretty easy. Have your users navigate to chrome://settings/content/flash and change the toggle for "Ask first" to move the slider to the right, changing the color to blue. You can close the browser (or the settings tab) and Chrome will once again show a security prompt when it comes across a Flash application. That will let your webinar product work as it did last week.
[UPDATE: It looks like Chrome doesn't allow a click-through hyperlink to that Flash settings page. Probably a security consideration. Just copy the address and paste it into your browser. But that's one more thing that non-technical users are going to have to deal with!]