[BUG] Errors in iframes should be captured

[Khlick]

Describe the bug When an iframe loads, for example using d3.js to draw a figure, the preload vizzy mechanism adds the iframe to the DOM temporarily in order to gather the _fragments, or test if the source is a cross-origin frame. When the iframe is added and the src is loaded, errors may occur in the loading iframe due to the unspecified dimensions of the iframe.

Expected behavior Errors that arise during the discovery phase (preload) should be handled, but continued errors in the production phase should be reported.

Environment:

• OS: Any
• Browser: Chrome
• Reveal.js version: 5.1.0

Additional context None

[Khlick]

V1.1.8 seems to mitigate some errors by first injecting the css in the document head prior to preloading vizzy frames.