@zetmolm - I'm not overly keen on doing so to be honest. There are a bunch of complications around it - for instance it is only going to work if (a) the book has a stylesheet, and (b) each html page links to that stylesheet. I don't like the idea of adding a feature that only works "some of the time" and even more the fact that it is to workaround a bug in someone else's software that in all likelihood could get easily fixed in another version. I known absolutely nothing about FBReader but I would suggest either chasing up whoever develops that or find another bit of reader software. This just has a "too bespoke" smell to me.
Of course if it was me in your situation and there was no alternatives I would say to heck with it and add it, but I'm not, so I'm going to use that time on other things instead
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