I have several jobs building via subversion commit triggers.
The commit messages contain several lines with the majority in the following format:
Up to Jenkins version 1.651.1 + Subversion plugin 2.5.7, the build page displayed the commit message with several lines correctly under "change history".
After upgrading to Jenkins 1.651.3 + Subversion plugin 2.6 and now Jenkins 2.7.1 + Subversion plugin 2.6, the commit message is displayed as a single line.
For example, the commit message above would be displayed as follows:
Checking the html page source of the build page, it looks like the newline characters in the commit message are being generated as:
As a result, the commit message is being displayed as a single line.