You can’t lock a tab in Google Chrome, there isn’t an option for this. Some users want this feature – any tab can be closed accidentally by dragging which opens as a new window or want to remember particular tabs like Facebook, Twitter, YouTube when too many tabs are open. As extensions add features to the browsers, Lock Tab is an extension for Chrome that allows to lock tabs to prevent from accidental closing.
Prevent accidental closing of tabs in Chrome by locking them with Lock Tab
After installing the extension, a lock icon appears on Chrome’s address bar – it appears in grey color on New Tab Page and turns to blue for any tab that has any page open.
All you need to do is: navigate to the tab you want to lock and click on the blue-colored lock icon or use the keyboard shortcut Ctrl +Alt + L instead. The locked tab appears with a tab title “Locked:tab_title”. You can toggle locking and unlocking of tabs by clicking on the lock icon. But you can’t close a locked tab either by using a shortcut or with a mouse click, that’s the feature of the extension.
If you accidentally try to close a tab, you’ll get a dialog box reminding that page is locked, however you can leave that page by clicking Leave This page button or keep that tab/page open by clicking Stay on this page.
You can enable or select a new shortcut to lock pages from the extension options. This extension does have its limitations: you can’t lock special pages like Gmail, Chrome new tab page, Chrome extension page, where the lock icon appears in grey color as it can’t act on those pages.