Pdf.js: Highlight showing over text in IE, but works in Chrome/Firefox

[msladev]

There is a text that was highlighted but in IE the highlight is showing over the text and hiding the original text. However, in Chrome and Firefox the highlight works as expected. Screenshots are shown below.

In IE:

In Chrome:

Thanks,
MSLA-IT

[yurydelendik]

Could you provide link to the PDF document?

[msladev]

This is the link.

https://test.mslacms.com/mslacms/Doc/21207/14_22230000_31049_1_2_55020006_0_0_Capati_R_5502_25071mod.pdf

Thanks for the help,
MSLA-IT

[yurydelendik]

Duplicate of #3900

[yurydelendik]

IE does not implement blending modes. We need to report that to https://connect.microsoft.com

[msladev]

We tried the suggestion in #3900 but it still doesn't work. Should we include something in the compatibility.js as well?

[yurydelendik]

Not sure, as a prototype code snippet shall work in IE.

[msladev]

We got it working.

But we changed a different line of code.

Thanks,
MSLA-IT

[yurydelendik]

Here is voting for implementing this feature in IE:

https://status.modern.ie/compositingandblendingincanvas2d?term=globalCompositeOperation

[tbasse]

@msladev, your solution worked perfectly for us until we stumbled upon some PDFs which rendered other image and shape elements with a 50% transparency due to this change.

Example PDF: https://dl.dropboxusercontent.com/u/1652601/ht-1-handbook.pdf

We then moved the workaround to CanvasGraphics_beginAnnotation() and only apply it for IE so it only affects the text highlight and only when it needs to.

[lochstar]

Thanks @tbasse, works great.

[ArnoldFabasoft]

We had the same issue in our integration of pdf.js. We implemented the workaround of tbasse for internet explorer. Thanks @tbasse
Will this fix or an other implementation find a way into pdf.js? I want to modify the original code as less as possible.
Thx Stefan

[jeremypress]

@yurydelendik, would you be open to a contribution that implements this workaround? I highly doubt that Microsoft will be addressing this on their end.

[timvandermeij]

This workaround is not acceptable for in the core because we don't want browser-specific hacks in there, but it may be accepted if it can be feature-detected and placed in https://github.com/mozilla/pdf.js/blob/master/src/shared/compatibility.js.

[jeremypress]

Makes sense, thanks @timvandermeij!

[timvandermeij]

Closing IE11/Edge (non-Chromium-based) issues in response to #11211. Please note that, as outlined in https://github.com/mozilla/pdf.js/wiki/Frequently-Asked-Questions#faq-support, only bugs which completely prevent the library and/or the default viewer from running will be accepted.