Hot deployment (deploy directory) does not work for provisioned blueprints

Context

I tried to migrate a custom Karaf distribution from 4.2.8 to 4.3.3 (fileinstall version 3.6.4 -> 3.7.0). The distribution contains a blueprint (xml) file that is supposed to be handled by one of Karaf's custom ArtifactListener_s. This kind of deploment works for Karaf 4.2.8 but fails for 4.3.3.

Steps to Reproduce

On a vanilla Karaf 4.3.3

• place org.apache.karaf.features.cfg in etc directory (adds aries-blueprint to boot features)
• place client.xml in deploy directory (this is copied from examples/karaf-blueprint-example-client)
• do a clean start of karaf
• on Karaf shell, execute bundle:list | grep "client.xml"

Actual Results

No matching bundles are listed

Addendum: if a file in deploy is touched while Karaf is running, the blueprint gets deployed. This does not need to be client.xml itself, renaming deploy/README to deploy/README.txt also results in the blueprint getting deployed

Expected Results

karaf@root()> bundle:list  | grep "client.xml"
70 | Installed |  80 | 0.0.0   | client.xml

The XML file from deploy directory should be listed. Note: The bundle cannot start since it is missing requirements

Cause

Karaf updated its dependency on Apache Felix File Install. That project has introduced a regression (FELIX-6490, which I also reported) that breaks the hot deployment for files that require custom handlers (like blueprint)