In r41306, we converted LabKey trunk to use IntelliJ's directory-based project format. This will make it easier to manage the project and hopefully help us avoid the accidental changes that hit LabKey.ipr periodically (or at least make them easier to fix).

The impact of this will be minimal for most developers. Once you sync to this revision, you just need to re-create the workspace file and open the new project.
-Close project
-Copy <labkey_home>/server/.idea/workspace.template.xml to <labkey_home>/server/.idea/workspace.xml
-Open new project by selecting <labkey_home>/server

If you have customized your workspace somehow, you might want to convert those setting to the new project.
-Delete <labkey_home/server/.idea if it exists
-Open project using LabKey.ipr (may need to fetch r41305 to restore this file)
-File | Save as Directory-Based Format
-Close project
-Delete everything in <labkey_home>/.idea except for workspace.xml
-SVN update
-Open new project by selecting <labkey_home>/server

We will leave the old project files in place for a week to ease the transition. The ipr and the iws template will be removed after that.

References:
https://www.jetbrains.com/idea/help/project.html#ProjectFiles
https://www.jetbrains.com/idea/help/converting-projects-into-directory-based-format.html
https://www.labkey.org/wiki/home/Documentation/page.view?name=build#intellij