Thank you, Pat! I super appreciate your help. This code is populating the UI field when there is a resize event, but the UI field is empty on load until there is a resize event. For my use case, I need to capture the width on load without a resize event.
I don’t know if this applies, but I discovered that if you’re trying to do dynamic sizing things on page load, if the page is long enough to cause an up/down slider to appear on the right side of the screen, the sizing seems take into account the page width before the slider appears, not after, and I can’t find any way to cause it to consider the width of the scrollbar if it appears.
To account for this, I just always show the vertical scrollbar no matter what:
/*Fix for top navigation bar resizing after a scrollbar is later loaded on the window that would cause navigation bar overlap on the page */
html {
overflow: -moz-scrollbars-vertical;
overflow-y: scroll;
}