jupyterlab 无法显示 png 图像:

结果只显示标题。
我有以下安装
JupyterLab v0.35.4
Known labextensions:
app dir: /anaconda3/envs/learnco_projects/share/jupyter/lab
@jupyter-widgets/jupyterlab-manager v0.38.1 enabled OK
@jupyterlab/toc v0.6.0 enabled OK
@mflevine/jupyterlab_html v0.1.4 enabled OK
@ryantam626/jupyterlab_code_formatter v0.1.9 enabled OK
jupyterlab-flake8 v0.2.4 enabled OK
Run Code Online (Sandbox Code Playgroud)
感谢您的帮助