Custom state causes error with initImplicitFlow and Microsoft Azure AD B2C

[merken]

Package version 3.1.4

When calling initImplicitFlow(route:string) using Azure B2C OpenId, the state is URL encoded.
This causes issues at the side of Microsoft.

See the generated URI from createLoginUrl :
https://login.microsoftonline.com/merken.onmicrosoft.com/oauth2/v2.0/
authorize?p=b2c_1_mrkn_si&response_type=id_token%20token&client_id=454caa98-b525-4c00-8e01-fc1e7bf477e4&
state=Z6wkN5gVwAozqZNIgaGUg7h1QJKfD4kMcxKyxmkq%3B%2Ftasks&
redirect_uri=https%3A%2F%2Flocalhost%3A3000%2Findex.html&scope=openid%20https%3A%2F%2Fmerken.onmicrosoft.com%2Fauthapp%2Fread_write&nonce=Z6wkN5gVwAozqZNIgaGUg7h1QJKfD4kMcxKyxmkq

The route was '/tasks', as a result %2Ftask is added to the state, the OpenId service fails to login.

Without state, the login succeeds :
https://login.microsoftonline.com/merken.onmicrosoft.com/oauth2/v2.0/
authorize?p=b2c_1_mrkn_si&response_type=id_token%20token&client_id=454caa98-b525-4c00-8e01-fc1e7bf477e4&
state=04iHQ6HqqZMQBqGnHSNkqh6fOTJnptmzuCwwq7kl
&redirect_uri=https%3A%2F%2Flocalhost%3A3000%2Findex.html&scope=openid%20https%3A%2F%2Fmerken.onmicrosoft.com%2Fauthapp%2Fread_write&nonce=04iHQ6HqqZMQBqGnHSNkqh6fOTJnptmzuCwwq7kl

Suggestion: maybe base64 encode the complete payload, this will likely not generate any characters subject to URI encoding.

[TomWeps]

We had a similar problem. The proposed pull request is here: #224

[manfredsteyer]

@TomWeps thx for the PR. It's merged and it will land soon.