css pseudo element (triangle outside the tr) position misaligned when scrollbar appears

Question

I have a panel which height is fixed and overflow-y:auto; in this panel I am displaying table and when user click on one of the row, triangle on right side of

Answer 1

If you apply position: relative to the table element, the arrow won't escape the container. For some reason the spec says a position: relative on table-row and other table elements are undefined.

Here's the spec for more info: https://www.w3.org/TR/CSS21/visuren.html#propdef-position