@martijnbraam GTK prefers GLES over GL these days and GLES 3.0 is the baseline now, like in Firefox (which never enabled HW acceleration for GL(ES) 2.x).
I can see that this is quite unfortunate for the PinePhone and Librem 5. But then GLES 3.0 is almost 13 years old and even a Thinkpad x220 from ~2012 supports it just fine - and that certainly doesn't count as "latest and greatest Macbooks".
AFAIK there's a certain chance that etnaviv will support GLES 3.0 eventually on the Librem though