This answer applies to all releases of Tau2, Tau, Quark2, Quark, and legacy Photon cameras.
This is not a bug. A black border is to be expected when using the PAL video format in any of FLIR`s OEM camera products. The PAL output from a FLIR camera is an adaptation of an NTSC image that is made to fit in the PAL video standard. The chosen method of achieving this fit was to add a black border around the outside of the image to adjust for the larger resolution for PAL. The alternative option was to replicate pixels and stretch the image to fill the larger format, but FLIR elected not to use this method, and has no plans to change the way PAL video is generated.