There are extensions that are legitimate but can't be installed from Google's Play store because it breaks policy. For example YouTube options (https://spoi.com

There are extensions that are legitimate but can't be installed from Google's Play store because it breaks policy. For example YouTube options (https://spoi.com/software/yto/ https://spoi.com/software/yto/), or the LastPass binary extension (might be wrong on that one). Thanks to the toolbar-installing software on windows it gives a legitimate reason to Google to close the system down a bit more.