'The JS action matches this string, so do that'. I further suspect that the whitelisted actions are all hard-coded behavior on the back end.

but they probably don't include one that changes the OCG state of the document. No idea what those specific actions might be. PDF.js has a 'white list' of javascript actions that are permitted.

PDF.js is the open source PDF renderer used by chrome (and probably firefox and several others). 'PDF.js' does support Optional Content Groups.I'm guessing this would work fine for everyone who was using Reader as their in browser viewer, and break for (almost?) everyone else. OCGs strike me as a feature that would have, at best, mixed support across browsers' native PDF renderers, to say nothing of properly executing their JavaScript. And I'm pretty sure you can use JS to detect when a PDF is viewed in a browser. IIRC, you can also toggle OCGs visibility with JavaScript. Hope I'm not SOL on opening PDF links in Chrome via Foxit. I searched these forums for 'Chrome Extension' with 0 results. I searched Chrome Extensions site for 'Foxit' and found nothing. Save the PDF and then opening in Foxit is a pain. Various Adobe products could probably do it natively, but you may need a copy of Acrobat to perform the necessary changes. I hate the built-in PDF viewer in Google Chrome. Whatever was generating the PDF would have to be pretty damn PDF-savy as well. You could then create a second version of that text that would appear over the first with your desired colors/background/anything/at/all. If the browser views are sophisticated enough, they should be able to handle Optional Content Groups (OCGs).

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