Shiny Tab, once installed, will give you curated calming wallpapers. It also shows your to-do list in full screen mode to improve user productivity. However, this extension has been found to be a browser hijacker that will attempt to commandeer one’s browser search and homepage. This browser hijacker will send you to malicious websites to get money from you or infect your computer further. It may also prevent you from changing your settings back.
Shiny Tab is usually installed through bundled software without you knowing. Remove it immediately.