Disable This Site is trying to open this application prompt in Edge
The above-mentioned erroneous behavior seems to be of the same kind one observes when ‘switching apps’ and appears every time an external protocol is invoked. So, the user is prompted for confirmation. Do the following to disable it in Microsoft Edge: Open the Windows Registry Editor. For this, press Win+R in combination and in the ‘Run’ dialog box that appears, type ‘regedit’ and press ‘Enter’. In the window that opens, navigate to the following key –
Switch to the right-pane and double-click the key with the name – ExternalProtocolDialogShowAlwaysOpenCheckbox. If the entry is not visible to you, you need to create a new one.
Next, in the Edit String box that appears, change the default Hexadecimal value from 0 to 1. When done, close the Registry Editor and Exit. Finally, restart your PC. Since, you have enabled this policy, an external protocol confirmation prompt ‘Always allow’ should be visible to you. Check the box marked against this option to skip all future confirmation prompts for the protocol on the site. When you disable this policy, the ‘Always allow’ checkbox won’t be displayed and the user will be prompted for confirmation every time an external protocol is invoked.
Disable This Site is trying to open this application prompt in Chrome
To disable this prompt in Google Chrome browser, navigate to the following key: Change this value as follows:
DWORD (32-bit): ExternalProtocolDialogShowAlwaysOpenCheckboxValue Data: 1 (Hex)
Hope this helps.