HoldTab автор Mikhail Vyrtsev

Useful when you get used to open new tabs in background and want to delay tab loading to the moment when you activate it. For example when you want to open 10 tabs with autoplaying videos or gif images but don't want them to start playing all at once. Basically the behavior is similar to "Load Tab on Select" extension.

To see the effect you should uncheck "When you open a link in a new tab, switch to it immediately" setting in the preferences.