Created by: deilv
On macOS and mobile devices the scrollbar is not part of the document, but rather floats above it. This means that it does not affect body/fixed element padding and scrollbarWidth is equal to 0.
The problem in #22332 (closed) was caused by the fact that the test expected padding-right to be increased while opening a modal, but threw an error when it was not (because padding + 0 = padding).
To address the issue the following changes have been made:
- A copy of the original getScrollbarWidth() function has been added (because the modal function is private)
- Tests now check if the padding or margin is changed as expected (even if zero) rather than just checking if it changed