Opera and Chrome - loads each TAB (can not turn off, there is no such functionality as in Firefox or Firefox(similar browser)
Why do many open (but not loaded eg. Firefox)?
Here I give answers:
I do not want to create thousands of bookmarks. I have them already too many.
The most important websites want to have just saved in the session (but without load each tabs)
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Chrome the
fastest browser, but it requires a lot of RAM but often memory failure
"Chicken Face" - idiotic message

Microsoft's new browser - Edge - though only theoretically good (I did not use, I do not have Windows 7 and probably does not have many extensions), it is still not able to convince users probably remember the worst of the Internet Explorer (version 6 or mostly).