vscode/extensions/github/markdown.css

/*---------------------------------------------------------------------------------------------
 *  Copyright (c) Microsoft Corporation. All rights reserved.
 *  Licensed under the MIT License. See License.txt in the project root for license information.
 *--------------------------------------------------------------------------------------------*/

.vscode-dark img[src$=\#gh-light-mode-only],
.vscode-light img[src$=\#gh-dark-mode-only] {
	display: none;
}