How are you a Moderator? This is an opera shortcut, it doesnt work on chrome, firefox, or edge. If you even tried to help you would of tried or googled if you even could do it on other browsers, or came across this post (https://forums.opera.com/topic/28906/closing-tab-using-shift-click) from your very own forum. There are other post like that scattered throughout here from the past years, but nobody seems to know a real fix.

Alt tab to switch windows, to which i click the tab i need to view and it closes because im still holding the alt key. i appreciate the inquiry on the reason why im pressing alt, but i dont see why it matters all that much. In the settings under shortcuts there is no option to change that hotkey. Is there another workaround to disabling that feature?

@leocg its not intentional. my thumb will still be on the alt key when i click to interact with my browser.

How do i disable closing a tab when you alt + left click it?

Now i know its as simple as "Just let go of the alt key when you switch windows" My brain and fingers don't work well together. I end up holding the alt button just a second too long and i click the tab i want to view and poof its gone. Its not normally an issue, except when im watching a video and i have to reopen the tab, then find where i was in the video.