WebHighlighter is a chrome extension written in vanilla JS without any third party libraries.It implements basic functionalities of a web highlighting extension.
The source code can be used by anyone willing to use it or modify it according to their needs. Basically this source code will serve as the perfect codebase to piggyback upon for anyone willing to make their own web highlighting extension.
I am using completely different approach from others as I am manipulating and breaking text nodes in the dom and this was somehow the most difficult part of all and had to make some workarounds to make it work perfectly. Manipulation of DOM causes problems that's why most people don't prefer to do it this way but I somehow managed to workaround those.
With time I will try to add comments to the code but till then bear with me please. Hope this source code helps you understand how Web Highlighting extension works.
I still believe that this code will have bugs and I am open to anyone willing to contribute to this extension.I am also looking for someone to improve its UI.