sentence highlighting not working on articles with math formulas.
fix findings from T229906.
Using production wikis:
Using https://pt.wikipedia.org/wiki/Special:ContentTranslation?title=Special:ContentTranslation&campaign=contributionsmenu&to=pt&page=Tensor+product&from=en&targettitle=Usu%C3%A1rio%28a%29%3ATestpitanormal%2FProduto+tensorial
- loading existing translation - doesn't show highlighting
- creating new translation - doesn't show highlighting
Using different language pair with the same Tensor product (`en` to `ca` )
- loading existing translation - doesn't show highlighting
- creating new translation - doesn't show highlighting
Using any different article with math formulas:
- loading existing translation - doesn't show highlighting
- creating new translation - doesn't show highlighting
Conclusion: it doesn't matter the MT engine nor the language, any article that has math formulas doesn't have highlighting available