dashboard: Kubeconfigs exceeding 4k do not work with the dashboard

Environment

Dashboard version: Dashboard Version: v1.8.3 ec1d7de4456e6a397c7f931f0a2bfc74a6ca2e9c 
Kubernetes version: 1.8.11 dc60726484f6e327640ce43d2fb164b726dd3c3d
Operating system: Oracle Linux
Node.js version: n/a
Go version: 1.10

Steps to reproduce

Load the dashboard, I will use kubectl proxy Navigate to http://localhost:8001 Click kubeconfig Load kubeconfig that is larger than 4096 bytes

Observed result

No error given in the UI, opening the console shows the following error: Cookie 'jweToken' possibly not set or overflowed because it was too large (4329 > 4096 bytes)!

Expected result

Login successful, redirected to dashboard

Comments

As far as I have seen, there is no documentation mentioning this 4k limit here or in K8s itself. Documenting this limitation would be the more critical issue. As a new feature, the Dashboard should likely support any kubeconfig regardless of the current browsers cookie size limit.