QGIS » QGIS Application

In QGIS 3.2.3 (and 3.2.2) and GRASS 7.2.2, the r.stats.quantile.out tool under GRASS Raster tools errors out. Here's the command that gets generated:

g.proj -c proj4="+proj=utm +zone=17 +datum=WGS84 +units=m +no_defs"
r.external input="/Volumes/raid6/XSACD/SAREM_examples/LaHabanaRS2TSXout/work/harbor_larger/TAJ_Diff_Image.tif" band=1 output="rast_5bc8bc96809672" --overwrite -o
r.external input="/Volumes/raid6/XSACD/SAREM_examples/LaHabanaRS2TSXout/work/harbor_larger/TAJ_Diff_Image.tif" band=1 output="rast_5bc8bc968260b3" --overwrite -o
g.region n=2560794.904281332 s=2554944.201572653 e=364022.01907411293 w=357514.2957052679 res=1.8934312973072467
r.stats.quantile -p base=rast_5bc8bc96809672 cover=rast_5bc8bc968260b3 quantiles=3 bins=1000 output="/var/folders/lc/ks3n63nd32jbj4ld050s40gcdkb4fm/T/processing_a5890a5c937a40878db6128e907be0e7/cce964f1604a4bf58168255bc3b77afd/output.txt" --overwrite

Here's a snippet of the output with the error:

r.external complete. Link to raster map <rast_5bc8bc968260b3> created.
ERROR: -p and output= are mutually exclusive
Execution of </var/folders/lc/ks3n63nd32jbj4ld050s40gcdkb4fm/T/processing_a5890a5c937a40878db6128e907be0e7/grassdata/grass_batch_job.sh> finished.
Cleaning up temporary files...

It seems to complete the raster processing, but the output directions in the command line are inconsistent. The -p flag calls for output of the statistics directly (into the command line/log?) whereas the GUI for the tool requires you to enter a temp or regular file. I've tried it every way including deleting the filename box, but get the same result each time.

I think the fix is easy - eliminate the -p flag from the command generator, but don't have a clue how to implement.