fix: customising cover page background colour not working

[cheng-kang]

Closes #666

Issue

marked@0.5.1 renders image without <p> wrapper, which is different from marked@0.3.12.

Solution

Updating match regex in _renderCover solves the problem.

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[QingWei-Li]

Good job.

FIY please use angular commit conventions.

[cheng-kang]

@QingWei-Li thanks, will do

[xunilog]

@cheng-kang . Issue still present in 4.9.1, cannot see this fix over there.

[danieldilly]

I just followed the Quick Start guide on the Official Website and I'm experiencing this issue. I can't change the background color or the background image.

[anikethsaha]

submit a fresh issue, with reproducible data. we can discuss there.

Thanks for pointing