API Monitor

Whether you're web developer and want to assess implementation correctness or just curious about how some site works, this tool adds additional panel to the browser’s DevTool that enables to see scheduled timeouts and active intervals, as well as to review and navigate to initiators of: eval, setTimeout, setInterval, requestIdleCallback, requestAnimationFrame and their terminator functions.

Allows:

• visit every function in the call stack (if available).
• detect eval ­function usage, see its argument and return value, same for setTimeout and setInterval when called with a string instead of a function.
• for every mounted video or audio media element's to see it’s state and properties, which media event was fired and how many times, plus toolbar to apply common actions.

Helps to spot:

• incorrect timeout delay, marked with ⁉️ (rare, critical).
• bad handler for terminator function, marked with ⁉️ (common, arrogant - please read the documentation).
• terminating non existing or elapsed timeout, in that case the delay will be shown as "N/A" (common, innocent).
• invocations from external domains.
• usages with extremely short delay causing high CPU usage with extremely low impact. The emphasis here is to lower the CPU usage to conserve energy and to use right and modern API for the purpose.
• usages with high amount of active timers (> 1000) that can be written just as one timer that starts the desired sequence (chatgpt.com).