Function isStillLoadingError

src/inject/dynamic-theme/style-manager.ts:470–472

(error: Error)

    // `sheet` property is not null,
    // but `cssRules` access error is thrown
    function isStillLoadingError(error: Error) {
        return error && error.message && error.message.includes('loading');
    }

    // Seems like Firefox bug: silent exception is produced
    // without any notice, when accessing <style> CSS rules