@SmokeDetector Everything here about GeoGebra was added by a moderator. The complication is that the post author is affiliated with GeoGebra. His
about popup says that he is "connected with … the new Relation Tool … and symbolic locus/envelope computations" and he "manage[s] our automated build system", which is, IMO, enough to require disclosure of affiliation, yet it was a moderator who added all of the text about GeoGebra into this answer. I've custom flagged.