Lock Tab is a Chrome extension that locks any open tabs from being closed accidently with a simply hotkey, Ctrl+Shift+L by default.
Once installed, it adds a little blue lock in the address bar right next to the bookmark’s star icon. Clicking it to tog the lock on and off to the current opening tab. When the page is locked, it also adds text “Locked:” in front of the page’s title indicating the tab is currently locked.
And of course, you can also use the quick hotkey to do the same. You can change the hotkey setting from the option page, which can be opened by right clicking on the lock icon.
One thing about this extension is that it does not only lock the current opening tab, but also locks automatically any new tabs opened from it. This is a nice feature that makes this extension a lot more useful. Locking only one tab doesn’t make too much sense, since the accidently closed tab can be easily reopened through Recent closed section on the preview page. But locking any new tabs from the locked tab would be much useful for sure.
A popup box will prompt if you want to close a locked tab, providing options to force close the tab or keep staying on the tab.
Not all pages in the tab can be locked. If you see the lock icon in grey, that means you won’t be able to lock the current page you are reading. For example, pages like Chrome new preview page, extension page, and Gmail cannot be locked.
Chrome’s new Pinned Tab feature seems to be doing the similar thing as this extension does. Because of this, the author of Lock Tab extension may not update the extension from this point on. However, as the author pointed out, the pinned tab still can be closed by keyboard shortcut or right mouse click but they can’t when locked by Lock Tab.