In org.openjdk.jmc.rcp.product/build.properties, we define the property
root.folder.dropins=rootfiles/dropins

This is supposed to lead to that the dropins folder plus the file it contains is included in the JMC product zip.
This is however not the case.

(I discovered this when I wanted to include a "build.info" file also in rootfiles, as part of JMC-5779)

Tycho is supposed to support root-properties, but maybe they need to be defined in another feature than the current??

See also
http://help.eclipse.org/oxygen/index.jsp?topic=%2Forg.eclipse.pde.doc.user%2Ftasks%2Fpde_version_qualifiers.htm
https://www.eclipse.org/tycho/sitedocs/BuildProperties.html