We sometimes see this bar "A plugin (shockwave flash) is not responding" on web pages which often freezes the page.
While trying to debug it, I can't figure out who is calling this shockwave flash, Are there any tools that can give a clue who initiated this or any flash?
Are there any tools that can give a hint of what is the cause of this?
Are there any tools that can give a hint of what is the cause of this?
You can try installing the Flash Player Debugger version which might give you hint messages.
See this Adobe guide for setting up in Chrome browser. Also you can try the 2015-dated solutions in this other Question.
...what is the cause of this?
Usually it's the running code in the SWF (Flash file) that causes this error. Not so much caused by an external caller/callee of the SWF.
For example : A while loop that does not get all required conditions to end/break will run forever (freezing the system) so browser eventually gives you the timeout error & option to stop plugin as shown in your image.
Other examples include code that should really be in a try / catch format but if there's only some "do this task" command & no error is caught or handled then the app is stuck for a long time.
