Try any devtools version using this Dev Tools App
Dev Tools App Application
developer options
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Source Manifest.json
{"update_url": "https://clients2.google.com/service/update2/crx",\t"name": "Dev Tools App",\t"description": "Try any devtools version using this Dev Tools App",\t"version": "1.39",\t"app": {\t\t"background": {\t\t\t"page": "background.html"\t\t}\t},\t"permissions": ["webview", "http://src.chromium.org/", "clipboardWrite"],\t"icons": {\t\t"16": "devtools16.png",\t\t"128": "devtools128.png"\t},\t"manifest_version": 2}
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