GitHub GraphQL API Explorer resets query variables pane on making any change in query

I am experimenting with GitHub GraphQL API through Explorer on I have been facing an issue where whatever I enter into the query variables pane is reset on making any change in the query pane.

I have attached a GIF here which demonstrates this bug:
I have a variable (number_of_repos) set in the variable pane initially. Now, on making a change in the query the variable pane is empty and my query fails. I have replicated this on the latest versions of both Chrome and Safari.

chrome-capture (1)

Any help in fixing this is highly appreciated. Thanks.