background capabilities is 0 for all browsers. there were other weird inconsistencies as well. We can completely leave to the side that your weighting scheme is surely arbitrary or perhaps even biased.

Because they're experimental. Since that's confusing even with a key, it may be better to hide experimental features/categories by default.

> We can completely leave to the side that your weighting scheme is surely arbitrary or perhaps even biased.

Hover on any number to see both "raw" and "with experimental/non-standard features" scores. If you do this to the overall score, you'll see that Firefox benefits the most from this.