Offline exporting: workaround for previous browser bugs no longer needed

[Tankzor]

Highcharts.svgToDataUrl (modules/offline-exporting.src.ts)

Expected behaviour

A CSP blocking "data:" scheme for img-src would still allow image export via "blob:"

Actual behaviour

Export fails in Firefox and (presumably) Safari, due to a workaround put in place for previous browser bugs.

// Safari requires data URI since it doesn't allow navigation to blob
// URLs. Firefox has an issue with Blobs and internal references,
// leading to gradients not working using Blobs (#4550)

Previous issue #4550 highlighted an issue with Firefox not handling internal references correctly, workaround was to fallback to "data:".

This has subsequently been fixed in Firefox. Related bugs:
https://bugzilla.mozilla.org/show_bug.cgi?id=841920
https://bugzilla.mozilla.org/show_bug.cgi?id=1280584
https://bugzilla.mozilla.org/show_bug.cgi?id=1447262

Also, there's a workaround in there for Safari with comment saying Safari does not allow navigation to "blob:", which I believe is also fixed (based on discussion in this issue, but I don't have a mac to check): https://bugs.webkit.org/show_bug.cgi?id=102914

Affected browser(s)

Firefox & Safari (?)

[Tankzor]

here's a sample with a CSP, PNG export fails in Firefox/Safari (confirmed): http://www.tests.massivedev.com/highcharts/csp/

[Tankzor]

Quick update: I was able to make it work in Firefox by butchering the .IndexOf("") string to not match firefox (in the minified file) as a sort of proof the workaround is no longer needed.

Also I was able to make it work in Safari as well by doing a similar thing, but I also had to remove the ";charset-utf-16" from the mime-type to make it work in Safari - which could introduce other issues, I have no idea..

http://www.tests.massivedev.com/highcharts/csp/2/

Sorry, quite a hacky way to do it, but I hope it proves the workaround is no longer needed at least for Firefox..

[sebastianbochan]

Hi @Tankzor,
Thank you for reporting about the problem.

FYI @oysteinmoseng

[stale]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions!

[Tankzor]

stalebotnothankyou