The icons become arrows in slides panel

[Ouch1978]

Hi,

I do like the blue and orange icons.

However, my icons display like this:

There's the same issue on vscode-reveal v4.0.3.

But seems vscode-reveal (PREVIEW) working well on my machine.

Would you please assist?

My VSCode version: 1.58.2 reveal-markdown: 2.0.1