I'm assuming this issue was caused when the 'Open Remote File' button was added to the start center.
Build ID: 7d3fa6bae9f7a755eb2d0ca24bf1afd5f3646bb7
TinderBox: Linux-rpm_deb-x86_64@70-TDF, Branch:master, Time: 2015-08-09_09:32:20
Locale: en-US (en_US.UTF-8)
Maxim Monastirsky committed a patch related to this issue.
It has been pushed to "master":
tdf#93310 No top margin for "Open Remote File"
It will be available in 5.1.0.
The patch should be included in the daily builds available at
http://dev-builds.libreoffice.org/daily/ in the next 24-48 hours. More
information about daily builds can be found at:
Affected users are encouraged to test the fix and report feedback.