I can transfer data with it as I just did to post a screenshot here - so it should.
Interestingly ~$ sudo mtp-detect gives
libmtp version: 1.1.21
Listing raw device(s)
Device 0 (VID=18d1 and PID=4ee1) is a Google Inc Nexus/Pixel (MTP).
Found 1 device(s):
Google Inc: Nexus/Pixel (MTP) (18d1:4ee1) @ bus 1, dev 6
Attempting to connect device(s)
libusb_claim_interface() reports device is busy, likely in use by GVFS or KDE MTP device handling alreadyLIBMTP PANIC: Unable to initialize device
Unable to open raw device 0
OK.
In fact it is the FP3+ though.
Still there is
$ adb devices
List of devices attached
an empty list.
Astoungingly after adding adbusers to the groups of my user ~$ lsusb still gives
[...]
Bus 001 Device 006: ID 18d1:4ee1 Google Inc. Nexus/Pixel Device (MTP)
[...]