That's interesting. The approved guidelines use the underscore; the draft guideline that was submitted was changed by the author after FPC had already approved it and written it up:

https://fedoraproject.org/w/index.php?title=User:Patches/PackagingDrafts/Web_Assets&action=history

https://meetbot.fedoraproject.org/fedora-meeting-1/2013-08-15/fedora-meeting-1.2013-08-15-15.33.log.html

I'll go ahead and fix this, since there's little point in having a guideline which doesn't match reality even though I actually disagree pretty strongly with using a hidden directory here.

I've changed both occurrences of _sysassets in that section to .sysassets and I'll go ahead and close this out. If other FPC folks want to weigh in, though, feel free to reopen.

Not sure how much it matters, but it'd probably be better to use _sysassets so the dir isn't "hidden" ... but not sure if we can change the package at this point.

The underscore was changed to a dot at the request of the Debian JavaScript Maintainers team. They were concerned that their implementation with some web servers in Debian might result in _sysassets being displayed in directory listings, which they wanted to avoid to reduce the chance of off-origin requests.

Please note that in Fedora this is implemented as an httpd alias, so in practical terms the directory is no more or less "hidden" if we use an underscore or a dot. We do not ship any hidden dot-prefixed directories in any web-assets-* package.