Function getRulesOrError

src/inject/dynamic-theme/style-manager.ts:456–465

()

    }

    function getRulesOrError(): [CSSRuleList | null, Error | null] {
        try {
            if (element.sheet == null) {
                return [null, null];
            }
            return [element.sheet.cssRules, null];
        } catch (err: any) {
            return [null, err];
        }
    }

    // NOTE: In Firefox, when link is loading,
    // `sheet` property is not null,