NOTE FROM MAINTAINER: 

This issue has been filed with the github-api maintainer: https://github.com/github-api/github-api/issues/780

Rolling back to github-api 1.106 addresses this issue in the short term. 

Grab the 1.106. version of the plugin from  

http://updates.jenkins-ci.org/download/plugins/github-api/

Then go to manage plugins > Advance > Upload Plugin and upload the 1.106 plugins and install it. All dependencies and indirect dependencies will also be satisfied with this version.

When trying to create a pipeline with blueocean, I enter my personal access token and choose connect. I get the following logged to console.

Unhandled Rejection: "Error: fetch failed: 500 for http://<ip>:8080/blue/rest/organizations/jenkins/scm/github/validate/?apiUrl=https://api.github.com\n at FetchFunctions.checkStatus (http://<ip>:8080/adjuncts/43befe0e/io/jenkins/blueocean/blueocean-core-js.js:54923:25)"

Not really sure how to debug this. There is no sign of it in jenkins logs. This only occurs when I enter a valid personal access token. If I enter gibberish, it correctly tells me it's an invalid token.