vim-anywhere is described as 'Sometimes, you edit text outside of Vim. These are sad times. Enter vim-anywhere!' and is an app in the Office & Productivity category. There are 2 alternatives to vim-anywhere for a variety of platforms, including Google Chrome, Linux, Mac, Vivaldi Browser and Windows. The best alternative is Surfingkeys, which is both free and Open Source.
wasavi is an extension for Chrome, Opera and Firefox. wasavi transforms TEXTAREA element of any page into a VI editor, so you can edit the text in VI. wasavi supports almost all VI commands and some ex commands.
Wasavi vs vim-anywhere opinions
pros, cons and recent comments
xlin Adds Vi emulation directly within text boxes, but only works online.