/api/v1/apps errors with "Invalid value for header: content-type", making impossible to login using any client (#1683) · Issues · Pleroma / pleroma

/api/v1/apps errors with "Invalid value for header: content-type", making impossible to login using any client

Environment

Installation type: From source
Pleroma version (could be found in the "Version" tab of settings in Pleroma-FE): 2.0.50-378-g7ee35eb9-develop
Elixir version (elixir -v for from source installations, N/A for OTP):

Erlang/OTP 22 [erts-10.6.4] [source] [64-bit] [smp:32:2] [ds:32:2:10] [async-threads:1]
Elixir 1.10.2 (compiled with Erlang/OTP 21)

Operating system: Linux
PostgreSQL version (postgres -V): 9.6.17
Instance: fedi.absturztau.be

Bug description

Steps to reproduce:

Enter fedi.absturztau.be in Tusky/Husky, BloatFE or Fedilab.
That's all, it doesn't work.

I've reproduced this with cURL as well:

curl -X POST "https://fedi.absturztau.be/api/v1/apps?client_name=123&redirect_uris=urn:ietf:wg:oauth:2.0:oob&scopes=read%20write%20follow"

/api/v1/apps responds with {"errors":[{"message":"Invalid value for header: content-type","source":{"pointer":"/"},"title":"Invalid value"}]}

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### Environment

* Installation type: From source
* Pleroma version (could be found in the "Version" tab of settings in Pleroma-FE): 2.0.50-378-g7ee35eb9-develop
* Elixir version (`elixir -v` for from source installations, N/A for OTP): 
```
Erlang/OTP 22 [erts-10.6.4] [source] [64-bit] [smp:32:2] [ds:32:2:10] [async-threads:1]
Elixir 1.10.2 (compiled with Erlang/OTP 21)
```
* Operating system: Linux
* PostgreSQL version (`postgres -V`): 9.6.17
* Instance: fedi.absturztau.be

### Bug description
Steps to reproduce: 
1. Enter fedi.absturztau.be in Tusky/Husky, BloatFE or Fedilab.
2. That's all, it doesn't work.

I've reproduced this with cURL as well:

```curl -X POST "https://fedi.absturztau.be/api/v1/apps?client_name=123&redirect_uris=urn:ietf:wg:oauth:2.0:oob&scopes=read%20write%20follow"```

/api/v1/apps responds with ```{"errors":[{"message":"Invalid value for header: content-type","source":{"pointer":"/"},"title":"Invalid value"}]}```

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