Initial editorState from $convertFromMarkdownString not formatting properly

[NikdokSVV]

I am using the following tranformers:

const customTransformers = [BOLD_STAR, ITALIC_UNDERSCORE, UNDERLINE, UNORDERED_LIST, ORDERED_LIST, LINK];

The following props to import strings and format them into markdown:

<LexicalComposer initialConfig={{ ...editorConfig, editorState: () => $convertFromMarkdownString(message ?? '', customTransformers) }}>

And the following onBlur function to update an external state with the new markdown text:

const handleBlur = (editorState) => {
    editorState.read(() => {
        const markdown = $convertToMarkdownString(customTransformers);
        console.log(markdown);
        setSomeState(markdown);
    });
};

When using the editor itself I am able to write the following: "This is a test" ("This is a" in bold, "is a test" in italic, and "is a" in bold italic). When inspecting and looking at the HTML elements that are generated I get the following:

<p dir="ltr">
    <strong class="editor-text-bold" data-lexical-text="true">This </strong>
    <strong class="editor-text-bold editor-text-italic" data-lexical-text="true">is a</strong>
    <em class="editor-text-italic" data-lexical-text="true"> test</em>
</p>

Looking at the markdown output from my onBlur I get the following:

**This _is a** test_

When bringing this markdown back into the editor at a later time, it is not formatted correctly. Can be tested the following way:

<LexicalComposer initialConfig={{ ...editorConfig, editorState: () => $convertFromMarkdownString("**This _is a** test_", customTransformers) }}>

It will appear like this: This _is a test_ (The italic is lost). How can I fix this?