| | 1 | I agree the issue is most likely with `Element.outerWidth()` after looking into this. |
| | 2 | |
| | 3 | Furthermore, jQuery themselves also discourage the "show and hide" method for calculating the element width. |
| | 4 | |
| | 5 | "jQuery will attempt to temporarily show and then re-hide an element in order to measure its dimensions, but this is unreliable and (even when accurate) can significantly impact page performance. This show-and-rehide measurement feature may be removed in a future version of jQuery." |
| | 6 | |
| | 7 | This is most likely due to UX and performance reasons and I don't feel this would be a good fix to the issue here. |
| | 8 | |
| | 9 | Additionally, while having the support for the "open" class would be nice, it still doesn't fix the underlying issue. |
| | 10 | |
| | 11 | |
| | 12 | I honestly have no idea how this could be reliably fixed without the collapse being opened by default. |