Improve spell checker please

[gnilsiu]

Right now the spell check feature underlines a misspelled word with faint red dotted lines, which is extremely hard to see on high resolution displays. Please consider using a more prominent way to highlight misspelt words.

Another request is for a search-and-replace type of spelling correction. Right now I need to scroll through the document and search for misspelt words line-by-line. A similar request also appeared here:

https://tex.stackexchange.com/questions/310358/spell-checking-in-texworks