Error in HTML Live Preview inside Komodo IDE

I am working on a webpage and I am previewing the HTML page inside Komodo IDE.

However, the webpage does not appear the same as it does in a web browser. There seems to be an issue with the clamp command.

For instance:

font-size: clamp(0px, 5vw, 38px)

Which rendering engine does the Live Preview in Komodo IDE utilize? Is it based on Blink, Gecko, or some other engine?

Should the preview in Komodo IDE resemble the appearance in Edge, Firefox, and Chrome? Am I making any mistakes?

I´m new to web coding and Komodo and I´m coding for fun and I´trying to learn.

Any help would be appreciated.

Komodo IDE version 12.0.1, Windows 11


Hi @sparqys,

Komodo 12 is build on top of Mozilla 35, which is very old now. It was released in 2015. I’d recommend previewing any of your HTML code in an external browser instead of the Komodo Tab.

FYI, development and support for Komodo IDE have stopped: ActiveState Komodo IDE Now Open Source

It’s now open sourced for the community to use as they like: ActiveState/OpenKomodoIDE: Open Komodo IDE is a fast and free multi-language code editor. Written in JS, Python, C++ and based on the Mozilla platform. (

1 Like

Thank you for letting me know!


Sure, take your time…I’ll back soon hope u will satisfied!!

The Live Preview feature in Komodo IDE typically uses a simplified rendering engine for previewing HTML pages, which may not fully support all CSS features or behave exactly like modern web browsers (such as Edge, Firefox, or Chrome).

In your case, the issue with the clamp command may be due to this simplified rendering engine not fully supporting it. To ensure your webpage appears correctly in modern browsers, you should periodically check it in actual browsers like Edge, Firefox, and Chrome.

Since you’re new to web coding and Komodo, it’s great that you’re coding for fun and trying to learn! As you continue, you’ll become more familiar with how different browsers render your code and how to address any compatibility issues that arise, here are some top-notch learning platforms for programming languages: 1. JavaPoint 2. Iqra Technology 3. W3School

These platforms offer excellent resources for mastering programming languages.