Fix grammar and improve consistency in CONTRIBUTING.md

Author: lejenhan

CONTRIBUTING.md

@@ -7,18 +7,18 @@ for a friendly and welcoming collaborative environment.
 
 ## Setting up a development environment
 
-Note: You will need NodeJS to build the extension package.
+**Note**: you will need Node.js to build the extension package.
 
 The `jlpm` command is JupyterLab's pinned version of [yarn](https://yarnpkg.com/) that is installed with JupyterLab. You may use
 `yarn` or `npm` in lieu of `jlpm` below.
 
-**Note**: we recommend using `mamba` to speed the creating of the environment.
+**Note**: we recommend using `mamba` to speed up environment creation.
 
 ```bash
-# create a new environment
+# Create a new environment
 mamba create -n notebook -c conda-forge python nodejs -y
 
-# activate the environment
+# Activate the environment
 mamba activate notebook
 
 # Install package in development mode
@@ -74,7 +74,7 @@ jupyter notebook
 
 The development installation described above fetches JavaScript dependencies from [npmjs](https://www.npmjs.com/),
 according to the versions in the _package.json_ file.
-However, it is sometimes useful to be able to test changes in Notebook, with dependencies (e.g. `@jupyterlab` packages) that have not yet
+However, it is sometimes useful to be able to test changes in Notebook, with dependencies (e.g., `@jupyterlab` packages) that have not yet
 been published.
 
 [yalc](https://github.com/wclr/yalc) can help use local JavaScript packages in your build of
@@ -117,20 +117,20 @@ There are also end to end tests to cover higher level user interactions, located
 
 ```bash
 cd ui-tests
-#install required packages for jlpm
+# Install required packages for jlpm
 jlpm
 
-#install playwright
+# Install Playwright
 jlpm playwright install
 
-# start a new Jupyter server in a terminal
+# Start a new Jupyter server in a terminal
 jlpm start
 
-# in a new terminal, run the tests
+# In a new terminal, run the tests
 jlpm test
 ```
 
-The `test` script calls the Playwright test runner. You can pass additional arguments to `playwright` by appending parameters to the command. For example to run the test in headed mode, `jlpm test --headed`.
+The `test` script calls the Playwright test runner. You can pass additional arguments to `playwright` by appending parameters to the command. For example, to run the test in headed mode, `jlpm test --headed`.
 
 Check out the [Playwright Command Line Reference](https://playwright.dev/docs/test-cli/) for more information about the available command line options.
 
@@ -163,7 +163,7 @@ To learn more about Lerna caching:
 
 Often a PR might make changes to the user interface, which can cause the visual regression tests to fail.
 
-If you want to update the reference snapshots while working on a PR you can post the following sentence as a GitHub comment:
+If you want to update the reference snapshots while working on a PR, you can post the following sentence as a GitHub comment:
 
 ```
 bot please update playwright snapshots
@@ -173,11 +173,11 @@ This will trigger a GitHub Action that will run the UI tests automatically and p
 
 ## Code Styling
 
-All non-python source code is formatted using [prettier](https://prettier.io) and python source code is formatted using [black](https://github.com/psf/black).
+All non-Python source code is formatted using [Prettier](https://prettier.io) and Python source code is formatted using [black](https://github.com/psf/black).
 When code is modified and committed, all staged files will be
-automatically formatted using pre-commit git hooks (with help from
+automatically formatted using pre-commit git hooks with help from
 [pre-commit](https://github.com/pre-commit/pre-commit). The benefit of
-using a code formatters like `prettier` and `black` is that it removes the topic of
+using code formatters like `prettier` and `black` is that it removes the topic of
 code style from the conversation when reviewing pull requests, thereby
 speeding up the review process.
 
@@ -209,9 +209,9 @@ hook with `pre-commit install`, you can fix everything up using
 `pre-commit run --all-files`. You need to make the fixing commit
 yourself after that.
 
-You may also use the prettier npm script (e.g. `npm run prettier` or
-`yarn prettier` or `jlpm prettier`) to format the entire code base.
-We recommend installing a prettier extension for your code editor and
+You may also use the Prettier npm script (e.g., `npm run prettier`,
+`yarn prettier`, or `jlpm prettier`) to format the entire code base.
+We recommend installing a Prettier extension for your code editor and
 configuring it to format your code with a keyboard shortcut, or
 automatically on save.
 
@@ -238,12 +238,12 @@ Now open a web browser and navigate to `http://localhost:8000` to access the doc
 
 ## Contributing from the browser
 
-Alternatively you can also contribute to Jupyter Notebook without setting up a local environment, directly from a web browser:
+Alternatively, you can also contribute to Jupyter Notebook without setting up a local environment, directly from a web browser:
 
 - [GitHub CodeSpaces](https://github.com/codespaces) is directly integrated into GitHub. This repository uses the [pixi](https://pixi.sh/) package manager to set up the development environment. To contribute after the Codespace is started:
-  - Run `pixi shell` in a terminal to activate the development environment
+  - Run `pixi shell` in a terminal to activate the development environment.
   - Use the commands above for building the extension and running the tests, for example: `jlpm build`
   - To start the application: `pixi run start`. A popup should appear with a button to open the Jupyter Notebook in a new browser tab. If the popup does not appear, you can navigate to the "Forwarded ports" panel to find the URL to the application.
 - [Gitpod](https://gitpod.io/#https://github.com/jupyter/notebook) integration is enabled. The Gitpod config automatically builds the Jupyter Notebook application and the documentation.
 - GitHub’s [built-in editor](https://docs.github.com/en/repositories/working-with-files/managing-files/editing-files) is suitable for contributing small fixes.
-- A more advanced [github.dev](https://docs.github.com/en/codespaces/the-githubdev-web-based-editor) editor can be accessed by pressing the dot (.) key while in the Jupyter Notebook GitHub repository
+- A more advanced [github.dev](https://docs.github.com/en/codespaces/the-githubdev-web-based-editor) editor can be accessed by pressing the dot (.) key while in the Jupyter Notebook GitHub repository.