Instead of screensharing your slides when you give a talk over Zoom, have the attendees view them in their own web browser from your site. (Or download them and view them locally.)

(If it's not obvious why this is better, read my blog post.)

This package, when distributed with the slides, makes them follow a "leader"; that's you. When you switch your browser from one slide to another, all the followers' browsers will switch too.

But if one attendee wants to go back (or forward) they can do that too. Then their session becomes disconnected from the leader's. A box will appear in the upper-right corner, always displaying the number of the slide that the leader is currently presenting. When the attendee wants to catch up, they just click this box.

I wrote a followup blog post that explains in more detail what this does and how it works.

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