Bug 43818 – Lots of overlapping highlights painted when selecting MathML

• Status: NEW
• Component: MathML

[David Kilzer (:ddkilzer)]

Created attachment 64056 [details]
Test case

* SUMMARY
When selecting MathML, the selection highlights overlap quite a bit such that the formulae aren't readable after selecting them.

* STEPS TO REPRODUCE
1. Open the test case in a WebKit nightly build.
2. Hit Cmd-A to select all text on the page.

* RESULTS
Selection highlights overlap on many of the formulae so that it's impossible to read them while highlighted.

* REGRESSION
N/A

[Frédéric Wang (:fredw)]

I suspect this is a consequence of the implementation design to base the rendering on the existing HTML renderer. See http://ojanvafai.com/post/mathml-in-webkit for an alternative.

[Frédéric Wang (:fredw)]

Created attachment 208177 [details]
testcase ::selection

(In reply to comment #1)
> I suspect this is a consequence of the implementation design to base the rendering on the existing HTML renderer. See http://ojanvafai.com/post/mathml-in-webkit for an alternative.

An idea to fix (or improve) that with the current model: try to set ::selection { background: transparent; } on anonymous renderers. As an example, I attach a testcase that removes the selection background on MathML elements (not sure the rule reaches the anonymous renderers, so that should be done at the C++ level).