Description of the Change

Check post content not empty before parsing it with DOMDocument

Closes #288

Alternate Designs

Possible Drawbacks

Verification Process

Checklist:

• I have read the CONTRIBUTING document.
• My code follows the code style of this project.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I have added tests to cover my change.
• All new and existing tests passed.

Changelog Entry

Fix - Fatal error on tracking a post with empty content

Credits

Props @cadic