What's wrong with innerHTML?

Performance Overhead

Modifying elements with innerHTML involves completely re-parsing and rebuilding the internal HTML structure of the element. This can be computationally expensive, especially for large elements or frequent updates.

Fragmentation of Document Object Model (DOM)

Using innerHTML can lead to fragmentation of the DOM, as it creates a new parsing context. This can impact performance and make the code harder to manage.

Limited Control over Rendering

When using innerHTML to manipulate content, you're not in complete control of the rendering process. This might result in unwanted reflows or rendering issues.

Accessibility Concerns

Changing content using innerHTML might not be as accessible as using proper DOM manipulation methods. Screen readers and assistive technologies might not interpret changes made with innerHTML accurately.

Compatibility with Custom Elements

If your content includes custom elements or web components, modifying them with innerHTML might not trigger their lifecycle methods properly, leading to unexpected behavior.

Potential for Breaking Encapsulation

Directly modifying inner HTML can break the encapsulation of your components, especially in more complex applications using frameworks like React or Vue.js.

Conclusion

To mitigate these issues, it's often recommended to use proper DOM manipulation methods, like createElement, appendChild, setAttribute, and so on, which offer better control over your modifications and help maintain security and performance.