Show the outline in explorer view only when a markdown file is active about vscode-markdown

[yzhang-gh]

I tried but I find something strange.

package.json:

"explorer": [
    {
        "id": "mdOutline",
        "name": "Outline",
        "when": "resourceLangId == markdown"
    }

1. Open a folder with a Markdown file opened by default - No outline ❌
2. Switch to a .json file - No outline ✔
3. Switch to .md file - Has outline ✔
4. Switch to .json file - Has outline ❌

[hashhar]

That is odd. I guess it's a bug or maybe the way it is designed to work. Ping @Tyriar

[Tyriar]

I think @sandy081 worked on this

[MagicPro1994]

I don't know why but it works smoothly when you turn on "markdown.extension.preview.autoShowPreviewToSide": true.

[karbassi]

Fixed in #44