Styles include mandatory language setting (in edit style-font-language) and when a style is applied to text it overwrites language information with own setting which is a huge inconvenience especially if this text is multilingual. I'd like to have [undefined] setting for style, which applies formatting but leaves language information of the original text intact, ditto for character (font-character). Setting style language to [none] is not it, it removes language completely.

Come to think of it, linking formatting and language is not a good idea, they should be independent, and there is already a bug for that: https://bugs.documentfoundation.org/show_bug.cgi?id=151290 but maybe the workaround I suggest will be easier to implement?