[#1434] email highlighting

Fixes #1434 

~~Currently have a failing spec where searches return different results depending on case, though since authoring I think this is an existing problem.~~

Came across #1558 while working on this.
Use 2 (not 4) spaces for indentation.<br>Line is too long. [96/80]<br>Prefer single-quoted strings when you don't need string interpolation or special symbols.