1. Set a bookmark in your source file by pressing Ctrl+F2
2. Press enter
3. Goto to a few line below by arrow-down key.
4. Set a bookmark again with Ctrl+F2
5. Press enter a few time.
6. Navigate between bookmarks by pressing F2
This also sometimes causes IDE to crash.
IDE.exe 5.9.0 Build 2330 18.05.2007,03:17.