Typically it seems to poll window height/width vars in js. https://github.com/sindresorhus/devtools-detect https://github.com/sindresorhus/devtools-detect Anot

Typically it seems to poll window height/width vars in js. https://github.com/sindresorhus/devtools-detect https://github.com/sindresorhus/devtools-detect Another variant: https://stackoverflow.com/questions/7798748/find-out-whether-chrome-console-is-open/30638226#30638226 https://stackoverflow.com/questions/7798748/find-out-whether...