In Wikipedia on a browser, surrounding text by <span class="texhtml">...</span> in the wiki-markup for an article causes the surrounded text to be displayed in a serif font, contrasting with the default sans-serif article text. The mechanism for doing this is a line "span.texhtml{font-family:serif}" in the default stylesheet. But in the Android app (running the latest Android and the latest app on a new Samsung Note 4), the change to a serif font is lost. The surrounded text is shown in the same sans-serif text as the rest of the article.

This issue affects over 2000 Wikipedia articles that use this mechanism to display mathematics formulas in inline text with an appearance that is supposed to match that of <math>. When viewing these articles on the Android app, this issue causes the formulas to look incorrect, no longer matching the appearance of <math>.