Can confirm that setting `pango_context_set_round_glyph_positions` to TRUE as suggested by @nyamatongwe on #3701 fixes this.
So its important that others test if they have the problem and report yes/no and any other side effects they see so we can decide to change it, or if there are significant side effects of having it `TRUE` maybe ask Neil to adopt the Geany approach (make it a setting :-)