After upgrading Jenkins from 1.448 to 1.451 (with yum, upgraded plugins too) several parts of Jenkins have become unusable with error "No valid crumb was included in the request":
- When building, the log is unavailable, see console_log.png
- Once the build is done, the complete log is available, but the same error appears on the side console_side.png
- Builds cannot be launched anymore from the build page (The firebug error console displays the "No valid crumb was included in the request" error). They still can be launched from the dashboard though.
- Cannot add build steps (when choosing a build step type an error is reported in background), see add_build_step.png
- The page loads only partially (first half is permanently greyed out, see configuration.png). The firebug error console displays the "No valid crumb was included in the request" error.
- Cannot upgrade nor downgrade, see error shown plugins.png