Same issue here. From what I see, tooltip gets added to the container first, but then tether moves it back to the body here. I found that tether scans container and all its parent nodes up to the body, if it finds an element with a non-static position - it moves a tooltip (see here). In reality tooltip always ends up in the body, cause grid classes like .col-12 use relative position.
I found that tether have bodyElement option which can be used to specify which element the tether's should attach themselves to. The problem is that tether currently makes the assumption that all of its calculations must be relative to the body, So even if we will use this option the container element will have to be same size and position respect to the body.
Maybe Popper.js is more suitable than Tether.js?
Will be fixed by https://github.com/twbs/bootstrap/pull/22444
Closed and fixed by #22444
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I found that tether have
bodyElementoption which can be used to specify which element the tether's should attach themselves to. The problem is that tether currently makes the assumption that all of its calculations must be relative to the body, So even if we will use this option the container element will have to be same size and position respect to the body.Maybe Popper.js is more suitable than Tether.js?