Thank you for contacting.
Could you elaborate a bit more on how exactly you are opening the external web page? Knowing this will allow me to give the most appropriate solution for the matter. Thank you in advance.
Further, you can also check if using the Cordova InAppBrowser
won't fit in your scenario, as by default it has the back button implemented. You can check our sample app
for further guidance.
I am looking forward to your reply.
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