Metadata prompt on wrong folders

[softwareloop]

Description of the problem:

• Sometimes the metadata prompt appears on folders that are not managed by uploader-plus
• Sometimes the metadata prompt does not appear on uploader-plus folders.

Here is how to reproduce it:

• Set up an uploader-plus folder on documentLibrary/Agency Files/Contracts
• Visit that folder and upload a file. The metadata prompt appears correctly. Confirm and finish the upload.
• Visit another folder, e.g. Agency Files/Images and upload a file. The metadata prompt appears but should't.
• Still in Images, upload another file. This time the metadata prompt does not appear, correctly.
• Go back to Contracts. Upload a file. The metadata prompt does not appear, incorrectly.
• Still in Contracts, upload another file. This time the metadata prompt will appear correctly.

It looks like there's a "stickiness" in the metadata prompt. Once it's used on an uploader-plus folder, it's used for the next upload too, even if the folder this time is a regular non-uploader plus folder.
And same the other way round. If you've uploaded something on a regular folder and then move to an uploader-plus folder, the first upload doesn't show the metadata prompt.

Affected versions: 1.5, 1.6, 1.7-SNAPSHOT
Non-affected versions: 1.2

Something must have happened between 1.2 and 1.5, probably related to the support of the newer Alfresco versions.