gradio: raising `gr.Error` gives "Unexpected end of JSON input" in Colab notebooks

Describe the bug

raising the error is supposed to show a modal with the custom error message

instead the error modal says “Unexpected end of JSON input”

Is there an existing issue for this?

• I have searched the existing issues

Reproduction

import gradio as gr

def welcome(name):
    if name == "WTF":
      raise gr.Error("It doesn't work")
    return f"Welcome to Gradio, {name}!"

with gr.Blocks() as demo:
    gr.Markdown(
    """
    # Hello World!
    Start typing below to see the output.
    """)
    inp = gr.Textbox(placeholder="What is your name?")
    out = gr.Textbox()
    inp.submit(welcome, inp, out)

if __name__ == "__main__":
    demo.launch()

Screenshot

Logs

n/a

System Info

Gradio: 3.27.0
Google Colab ipynb

Severity

annoying