[BitBucket user: Sébastien Jodogne]
[BitBucket date: 2018-12-26.17:31:43]

Wow... impressive changeset... For reference, jQuery Upload could be upgraded from v5.32.0 to [v9.28.0](https://github.com/blueimp/jQuery-File-Upload/releases), which could fix your observed issue.

Furthermore, the [jQuery core](https://en.wikipedia.org/wiki/JQuery#Release_history) could be upgraded from v1.9.1 to either v1.12.4 or v2.2.4. Note that jQuery 3.x is known to be [incompatible](https://github.com/jquery/jquery-mobile/issues/8546#issuecomment-271163317) with jQuery Mobile <= 1.4.5.