partial merge of upstream/main

* leaving out DotStarHspi5MhzMethod, as we are still on NPB 2.6.9 for eth boards
* leaving out the index.css/index.css changes, as I'm not sure how to merge this.

@ewoudwijma we need to merge the JS and CSS parts when you are back; I'll stay with our MM version for now.

wled00/FX.cpp

@@ -4655,8 +4655,8 @@ uint16_t mode_2DColoredBursts() {              // By: ldirko   https://editor.so
     byte ysteps = abs8(x2 - y2) + 1;
     byte steps = xsteps >= ysteps ? xsteps : ysteps;
     //Draw gradient line
-    for (size_t i = 1; i <= steps; i++) {
-      uint8_t rate = i * 255 / steps;
+    for (size_t j = 1; j <= steps; j++) {
+      uint8_t rate = j * 255 / steps;
       byte dx = lerp8by8(x1, y1, rate);
       byte dy = lerp8by8(x2, y2, rate);
       //SEGMENT.setPixelColorXY(dx, dy, grad ? color.nscale8_video(255-rate) : color); // use addPixelColorXY for different look