JupyterLab Refresh View Extension

[!TIP] This extension is part of the stellars_jupyterlab_extensions metapackage. Install all Stellars extensions at once: pip install stellars_jupyterlab_extensions

JupyterLab extension that adds a "Refresh View" context menu command to reload file content from disk while preserving scroll position.

Features

The extension provides intelligent content refresh while preserving your exact position in the document. For notebooks, it identifies the visible cell in your viewport and automatically scrolls back to that cell after refresh, restoring both the cell position and viewport offset even when JupyterLab's windowed rendering progressively loads cells. For markdown and text files, it maintains precise scroll coordinates. The extension works seamlessly with jupyterlab_tabular_data_viewer_extension to refresh CSV and tabular data files in their custom viewer.

• Automatic Cell Scrolling - Identifies visible notebook cell before refresh and automatically scrolls back to it afterward, preserving exact viewport position
• Hybrid Position Tracking - Cell-based anchoring for notebooks with scroll coordinate fallback, ensuring position preservation regardless of content loading order
• Intelligent Stabilization - Monitors content loading and adaptively restores position as cells render, stabilizing within 300ms typically
• Tabular Data Viewer Compatibility - Works with jupyterlab_tabular_data_viewer_extension to refresh CSV files in custom tabular view
• Context Menu Integration - Right-click access for markdown files, notebooks, text editors, and tabular data viewers
• HTML Viewer Support - Refresh rendered HTML files by right-clicking the file's tab (the sandboxed iframe prevents an in-content menu)
• Command Palette Access - Available under "File Operations" category
• Smart Enable/Disable - Only active when a document with reloadable context is open

Use Cases

• Iterative Editing - Refresh files edited externally without losing your place
• Live Documentation - Keep markdown files in sync with external updates
• Collaborative Work - View changes from teammates without manual reload
• Build System Integration - Refresh generated files after build processes

Requirements

• JupyterLab >= 4.0.0

Installation

From PyPI

pip install jupyterlab-refresh-view-extension

From npm

jupyter labextension install jupyterlab_refresh_view_extension

Usage

1. Open a markdown file, notebook, or text file in JupyterLab
2. Right-click anywhere in the document content
3. Select "Refresh View" from the context menu
4. The file reloads from disk while maintaining your scroll position

For HTML files (rendered in the HTML viewer), right-click the file's tab and choose "Refresh View" - the rendered content sits in a sandboxed iframe where an in-content context menu cannot appear.

Alternatively, open the command palette (Ctrl+Shift+C or Cmd+Shift+C) and search for "Refresh View".

Uninstall

pip uninstall jupyterlab-refresh-view-extension

Contributing

Development install

Note: You will need NodeJS to build the extension package.

The jlpm command is JupyterLab's pinned version of yarn that is installed with JupyterLab. You may use yarn or npm in lieu of jlpm below.

# Clone the repo to your local environment
# Change directory to the jupyterlab_refresh_view_extension directory
# Install package in development mode
pip install -e "."
# Link your development version of the extension with JupyterLab
jupyter labextension develop . --overwrite
# Rebuild extension Typescript source after making changes
jlpm build

You can watch the source directory and run JupyterLab at the same time in different terminals to watch for changes in the extension's source and automatically rebuild the extension.

# Watch the source directory in one terminal, automatically rebuilding when needed
jlpm watch
# Run JupyterLab in another terminal
jupyter lab

With the watch command running, every saved change will immediately be built locally and available in your running JupyterLab. Refresh JupyterLab to load the change in your browser (you may need to wait several seconds for the extension to be rebuilt).

By default, the jlpm build command generates the source maps for this extension to make it easier to debug using the browser dev tools. To also generate source maps for the JupyterLab core extensions, you can run the following command:

jupyter lab build --minimize=False

Development uninstall

pip uninstall jupyterlab_refresh_view_extension

In development mode, you will also need to remove the symlink created by jupyter labextension develop command. To find its location, you can run jupyter labextension list to figure out where the labextensions folder is located. Then you can remove the symlink named jupyterlab_refresh_view_extension within that folder.

Testing the extension

Frontend tests

This extension is using Jest for JavaScript code testing.

To execute them, execute:

jlpm
jlpm test

Integration tests

This extension uses Playwright for the integration tests (aka user level tests). More precisely, the JupyterLab helper Galata is used to handle testing the extension in JupyterLab.

More information are provided within the ui-tests README.

Packaging the extension

See RELEASE