So when was it exactly? I doubt recently. Mesa progressed to the point of full compliance a few years ago. Today, it's trusted a lot more than the blob, due to

So when was it exactly? I doubt recently. Mesa progressed to the point of full compliance a few years ago. Today, it's trusted a lot more than the blob, due to the later silently swallowing errors frequently and messing around with substituting shaders behind the scenes. Try testing current Mesa versions. Previous experiences are no longer relevant.