# Highlight and add notes to NotebookLM sources

> Highlight and add notes to NotebookLM sources. Kortex gives each source in the Workspace a highlight color and a note, then filters by color.

https://www.kortex-notebooklm.com/features/source-highlights-and-notes

1.  [Features](/features)
2.  Highlights and notes on sources

Organize

# Highlights and notes on sources

Kortex lets you color-code and annotate the sources of your Gemini Notebook (formerly NotebookLM) notebooks in the Kortex Workspace. Each source can have one of eight highlight colors and a private note written in Markdown. You can then filter the Sources table by highlight color.

[Add to Chrome](https://chromewebstore.google.com/detail/kortex/hdapplggdhndkblofffknpmnnnnbncbn) [Follow the tutorial](/tutorials/how-to-highlight-and-annotate-notebooklm-sources)

[![The All Sources table in the Kortex Workspace with each source’s type, notebook, tags and folder.](/media/features/all-sources.webp)](/media/features/all-sources.webp)

Every source across your notebooks, with its tags and folder.

## What are highlights and notes on sources in Kortex?

Highlights and notes live in the Kortex Workspace. Each source can have one of eight highlight colors and a note written in Markdown. You can then filter the Sources table by highlight color.

## What you get

-   ### Mark what matters
    
    Pick a color for each source: red, orange, yellow, green, blue, purple, pink or gray. The row takes the color, so flagged sources stand out in a long table.
    
-   ### Your own words, next to the source
    
    Write key takeaways, a summary or a question about a source. A note icon shows in the row when a note exists.
    
-   ### Filter by color
    
    Use the Highlight Color filter to show only the sources you marked, or the ones with no highlight.
    
-   ### You decide what colors mean
    
    Use red for check this, green for done, or any code you like. Kortex does not give the colors any meaning.
    

## How do I highlight a source?

Open **Sources** in the Kortex Workspace. Every source from all your notebooks is in one table. Each row has a small color dot. Click it and a **Source Details** panel opens on the right. It has two parts.

**Row Status Highlight.** Eight colors: red, orange, yellow, green, blue, purple, pink and gray. A gray circle marked None clears the highlight. The whole row takes the color.

**Personal Notes & Thoughts.** A text box that accepts Markdown (a simple way to format text). Use it for key takeaways, summaries or questions about that source. **Save & Sync Notes** stores it. A note icon then shows in the row.

## How do I find the sources I flagged?

Add the **Highlight Color** filter to the Sources table. Then choose **Highlight is…** and tick colors, or **No highlight** to see what you have not sorted yet. The Notebooks table has the same highlight filter.

## Using it well

Decide what each color means before you start, and keep to it. A common set is red for unreliable, yellow for to read, green for cited. Use colors together with [tags](/features/tags-and-source-labels). Tags say what a source is about. Colors say where it stands.

## What it does not do

It does not edit the source or send the note to Gemini Notebook. The colors and notes live in Kortex and show in the Workspace.

## How it works

Want every step? [Follow the tutorial](/tutorials/how-to-highlight-and-annotate-notebooklm-sources).

1.  ### Open the Sources view
    
    In the Kortex Workspace, choose Sources in the sidebar to see every source across your notebooks.
    
2.  ### Click a row's color dot
    
    The dot beside a source is called Add highlight. Click it to open the Source Details panel on the right.
    
3.  ### Pick a color and write a note
    
    Choose a color under Row Status Highlight, or the gray None circle to clear it. Type in Personal Notes & Thoughts, then click Save & Sync Notes.
    
4.  ### Filter by highlight
    
    Add the Highlight Color filter and choose Highlight is, then one or more colors, or No highlight.
    

## Questions people ask

Something we missed? [Ask us](#contact).

### How do I clear a highlight?

Open the source's Source Details panel and click the gray None circle under Row Status Highlight. The row goes back to normal.

### Where do the highlights show?

In the Kortex Workspace, in the All Sources table and in a notebook's own source list. They do not show inside Gemini Notebook.

### Do my notes change the source?

No. Kortex stores a note next to the source. The source in Gemini Notebook does not change.

### How is a note different from a Kortex note?

A source note belongs to one source. You write it in the Source Details panel. Kortex notes belong to a notebook and live on its Notes tab, where New Note makes one.

### How many colors are there?

Eight: red, orange, yellow, green, blue, purple, pink and gray, plus None to clear.

### Can I color-code sources in NotebookLM?

Yes, in the Kortex Workspace. Click the color dot on a source row and pick one of eight colors. The color lives in Kortex and does not change the source in Gemini Notebook (formerly NotebookLM).

## Related features

The full reference is in the [Kortex docs](/docs/all-sources).

-   [Tags and source labels Colored tags for notebooks, and a separate set of tags for single sources.](/features/tags-and-source-labels)
-   [Global search One search box for every notebook, source, note, collection, tag and podcast.](/features/global-search)

[All Kortex features](/features)

## Try it on your own notebooks.

100,000+ people use the Kortex extension. Install it and try highlights and notes on sources on a notebook you already have.

[Add to Chrome](https://chromewebstore.google.com/detail/kortex/hdapplggdhndkblofffknpmnnnnbncbn)

100,000+ users, rated 4.5 on the Chrome Web Store.