Document library field value disappear when uploading new version. Reappears when edited.

When a new version of a document is uploaded to a Document Library the other field/column values disappear. If the document is edited in Word Online and saved the values reappear.

The image below shows Document library with Text field 1 and 2 populated.

The image below is after a new version of Document Four is uploaded. Content in Text field 1 and 2 are missing.

After Document Four is edited in Word Online the content of Text field 1 and 2 reappear.

Is this a bug that needs to be fixed by Microsoft, or is there something that I am missing?