Low-Latency HTML Canvas

Instead the hint tells the underlying system to skip as much compositing as it is able and in some cases, the canvas’s underlying buffer is sent directly to the screen’s display controller. Flicker can also occur when you clear the screen context in your own drawing code. For example, let’s say that I get a context and specify alpha as false, then somewhere later in my code I call a second time with alpha set to true as shown below.

Source: developers.google.com