long list of checkboxes throw fixed sidebar into "jump loop"

[rvdb]

Hi,

Does scrollToFixed have a problem with checkboxes? I have a long sidebar whose content overflows the available height, so the sidebar will have a scroll bar. I've noticed how the contents of that sidebar start to jump between the top and a scrolled down position, when:

1. it has been fixed with scrollToFixed (I mean, after its position has been fixed with scrollToFixed)
2. the contents of that sidebar is scrolled

After that, it keeps jumping up and down, as if it is stuck in a loop. I'm suspecting checkboxes could be the problem, since the sidebar behaves normally when I remove them (I mean, I can scroll it up and down when fixed).

To illustrate this, I've created a fiddle at http://jsfiddle.net/rvdb/Lr2czs4p/, based on the "position_with_floats" test file shipped with the scrollToFixed download.

Note: the problem only seems to occur with Firefox (47.0, I'm on Windows 7 Pro 64 bit); Opera and Chrome behave well. Yet, even when there's no "jump-loop" (by removing the checkboxes from my example), scrolling (either the fixed sidebar or the rest of the page) gets very slow (close to unresponsive) on Firefox, once the sidebar has been fixed with scrollToFixed. Are there known issues in Firefox with interference of other listeners for scrolling events?

Best,

Ron

[rvdb]

Ah, I've found a workaround: move the height and overflow properties from the sidebar div to the form inside it. See the updated JSFiddle at http://jsfiddle.net/rvdb/Lr2czs4p/1/.

This solves both the scroll jump loop, and the slow scrolling in Firefox.

[bigspotteddog]

Hi Ron,

Thanks for the workaround. I was not aware there was an issue with Firefox for what you describe.

I will put together a FAQ or something that refers to your workaround for this case.

Thanks again!

[rvdb]

You're welcome (and thanks for the wonderful plugin!). I realize this might be a very specific problem in a very specific context; if you need more details or clarification, I'm happy to help you out.