Last year I got myself a first pair of gore-tex B0 boots. Before I used only leather. I took care of those as good as I could. Keeping clean and using special sprays.
However now one boot developed 1.5 cm split in gote-tex surface. I tried to fix it with Sugru, a self-setting rubber that is advertised as able to fix mountaineering boots top. After an 8 hour hike on mixed terrain of trail, snow and rock it failed by breaking in multiple places and opening the split.
I would sew with glue a leather boot, but what should I do about gore-tex one?