Facebook Login Issue - Canopenurl: Failed for Url: "Fbauth2:///" - Error: "(Null)"

iOS 9 Facebook login simulator -canOpenURL: failed for URL: fbauth2:/// - error: (null)

Why do I see console messages like 'canOpenURL: failed for URL: "fb...://' or ?

This is an Xcode warning indicating the the canOpenURL: call returned
false. As long as you have configured the LSApplicationQueriesSchemes
entry in your plist as described above, you can ignore this warning.

-canOpenURL: failed for URL: fbauth2:/ - error: (null) for ios 9 (swift)

I think it all about the Facebook SDK. I also face this problem .So my suggestion is to use the latest Facebook SDK.If you are using only for login means - you can add coreKit,LoginKit and use fbauth2 alone for your problem.No need to add others items.Latest Facebook SDK. Or try to use the V4.6.0 SDK.Here is the link Older SDK

Hope this help

Facebook Login kit with iOS 13 canOpenURL: failed for URL: “fbauth2:///”

Upgrading to the current FBSDK should resolve the problem.

FBSDKCoreKit/FBSDKCoreKit/Internal/BridgeAPI/FBSDKBridgeAPI.m was modified to support iOS 13's requirement to implement ASWebAuthenticationPresentationContextProviding in FBSDKCoreKit 5.4. The current version is 5.8. Versions prior will no longer work.

The needed change is posted here: https://github.com/facebook/facebook-ios-sdk/commit/6b061099f339ef0e8bde2e2c2163ef5a3c1b8340#diff-72593591275d63edfb1bfad837e4c32f

Facebook SDK: app not registered as a URL Scheme

Follow these three steps:

Create a key called FacebookAppID with a string value, and add the app ID there.
Create a key called FacebookDisplayName with a string value, and add the Display Name you configured in the App Dashboard.
Create an array key called URL types with a single array sub-item called URL Schemes. Give this a single item with your app ID prefixed with fb. This is used to ensure the application will receive the callback URL of the web-based OAuth flow.

The finished .plist should look something like this:

Sample Image

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