[Bug] Issue about custom icons

[BTBMan]

I'm using the custom icons feature. when I put an icon collection file such as foo.json into the icons folder, It includes an icon bar: {body: 'xxx'}.

After that, When I use some APIs such as /collections?prefix=foo､ /collection?prefix=foo､ /foo.json?icons=bar, etc. They work fine.

But I deleted foo.json, and updated via the /update API. But It seems not updated. I can also receive the same responses via the APIs above. except /collections?prefix=foo, that's because it response is the icon info.

Expection

I hope it will return nothing after deleting the file.