vTabs brings vertical tabs to Google Chrome (with one caveat)
When you compare Google Chrome to Mozilla Firefox, you will notice sooner or later that Firefox supports displaying contents in a sidebar while Chrome does not.
The Firefox browser ships with options to display the History or Bookmarks in a sidebar natively and add-ons extend that functionality further. TreeStyleTab moves tabs from being displayed horizontally in the browser to the sidebar which is excellent not only because more tabs can be displayed at the same time on the screen with more information but also because the removal of the horizontal tab bar makes room for website content.
Chrome does not support sidebars but that does not mean that open tabs cannot be displayed vertically in the browser.
The free extension vTabs adds that functionality to the Chrome browser. Once installed it will display open tabs in an overlay on the left side of the browser window.
Doing so means that contents of the active site may be hidden underneath it and while that's not a problem on many sites on large enough screens, it causes issues on sites that are aligned to the left and not centered.
This is mitigated by the fact that you can hide and display the sidebar at any time. Still, that is, without doubt, the main caveat and what makes the solution inferior to the way tabs may be displayed vertically in Firefox.
On a widescreen monitor, it just makes so much sense to have a vertical tabs sidebar. I really wish Chrome had something built-in like this (if Vivaldi could get it right. being based on Chromium, so could Chrome!).
See https://www.ghacks.net/2014/10/30/vtabs-brings-vertical-tabs-to-google-chrome-with-on-caveat/