note plugin: Unexpected token o in JSON at position 1

[Mister-Hope]

reveal.js/plugin/notes/plugin.js

Lines 201 to 212 in 3786133

	// Keep listening for speaker view hearbeats. If we receive a
	// heartbeat from an orphaned window, reconnect it. This ensures
	// that we remain connected to the notes even if the presentation
	// is reloaded.
	window.addEventListener( 'message', event => {
	if( !speakerWindow ) {
	let data = JSON.parse( event.data );
	if( data && data.namespace === 'reveal-notes' && data.type === 'heartbeat' ) {
	reconnectSpeakerWindow( event.source );
	}
	}
	});

These lines are every UNRESONABLE, because window message event is not revealjs ifself.

I am not sure if you heard an extension called wappalyzer

It will trigger that event handler.

Also, there are other project like giscus, are using the message event listener either.

Reveal.js Note plugin should never make sure that event.data is a string, and it can be successfuly JSON.parse.

You probably need to add a try {} catch {} block, and make extra check before rudely JSON.parse it.

[Mister-Hope]

Here is a reproduciton link, and the console is just like a mess if you have some extension using that even installed, or with project like giscus.

https://vuepress-theme-hope.github.io/v2/md-enhance/guide/presentation/themes.html

[Mister-Hope]

Any update for this one? As fixing this should be easy.

[hakimel]

Thanks for the feedback—this has been fixed.