How I speed up passing a rainbow through text
I speed up my JavaScript animations of the color of each letter in lines of text by: using 'IntersectionObserver' to only run the animations when the text is visible coloring the elements for the letters in steps with delays in-between. (I also create and get references to these elements in steps) sometimes coloring whole lines rather than each letter sometimes just coloring lines that are 'above the fold' only slowly changing the colors of the letters (about every 20 seconds) sometimes not having a 'transition' for the color changes delaying the start of the coloring until a few seconds after the page loads making the page load quicker by making the page small by putting the JavaScript in separate files. I create 'script' elements in JavaScript and set their 'src'. I use 'load' events to create dependencies between the scripts not coloring the text on mobiles and tablets. I look at the 'user agent string' and use 'media qu...