front: update e2e tests readme

front/README.md

@@ -5,7 +5,7 @@
 - go inside `/front/` from OSRD main project
 - you'll need [`npm`](https://nodejs.org/en/download/package-manager) and
   [`yarn`](https://classic.yarnpkg.com/lang/en/docs/install/)
-- exec `yarn` (hope you have a good connexion and a good cup of tea)
+- exec `yarn` (hope you have a good connection and a good cup of tea)
 - exec `yarn start` (perhaps you'll need `NODE_OPTIONS="--openssl-legacy-provider"` if your node
   version is too new)
 - enjoy
@@ -39,15 +39,15 @@ Launches end to end tests.
 
 It requires:
 
-- Install playwright dependencies `cd ./front/ && yarn playwright install --with-deps`
+- Install Playwright dependencies `cd ./front/ && yarn playwright install --with-deps`
 - Backend containers to be up: `docker compose up --no-build --detach valkey postgres gateway core editoast`
 - Running front with `docker compose up --build --detach front`
 
 Now you can run the test with `cd front/ && yarn e2e-tests`.
 
-If you are using a Linux distribution not supported by playwright (which only supports Windows, macOS and Ubuntu/Debian),
-you can instead start the tests inside a docker container using `osrd/scripts/run-front-playwright-container.sh`.
-You may pass the same options and arguments to this script as you would to `yarn e2e-tests` or `yarn playwright test`.
+If you are using a Linux distribution not supported by Playwright (Playwright only supports Windows, macOS and Ubuntu/Debian),
+you can start the tests inside a Docker container using: `osrd/scripts/run-front-playwright-container.sh`.
+This script accepts the same options and arguments as `yarn e2e-tests` or `yarn playwright test`.
 
 > [!CAUTION] If you try to run `yarn start` instead of running it through docker, you'll notice it
 > doesn't work because the gateway can't access your local port from inside a container. 2
@@ -57,14 +57,19 @@ You may pass the same options and arguments to this script as you would to `yarn
 > - if on Linux, you can also launch all the containers on the host network: you can replace the
 >   `docker compose <something>` above with `osrd/scripts/host-compose.sh <something>`
 
-If the tests fail, you'll find a `front/test-results` folder that will contain videos of the fail
-test executions. They might be of help to understand what's going on. Note that the CI also exports
-these videos as artifacts.
+If the tests fail, a `front/test-results` folder will be created, containing videos and traces of the failed test executions.
+These files can help you understand what went wrong.
+Additionally, the CI system exports these videos and traces as artifacts.
+You can view the trace files using the [Playwright trace viewer](https://trace.playwright.dev/).
 
-You may also want to explore the documentation of the test framework
-[Playwright](https://playwright.dev/). For example, try launching each test independently using
-`yarn playwright test --ui`, debug a test with `yarn playwright test --debug`, or launch a specified
-test of a specified test file with a specified browser once with for example
+If visual comparisons tests fail due to UI changes, new snapshots are required as the baseline.
+You can automatically update snapshots by running tests with the `--update-snapshots` flag:
+`yarn playwright test --update-snapshots`
+
+You may also want to explore [Playwright documentation](https://playwright.dev/docs/intro) for more insights.For example:
+Launch each test independently using: `yarn playwright test --ui`.
+Debug a test with: `yarn playwright test --debug`.
+Run a specific test in a specific test file with a specific browser and no retries using:
 `yarn playwright test 011-op-times-and-stops-tab.spec.ts -g "should correctly set and display times and stops tables" --project=firefox  --retries=0`.
 
 ## Design rules
@@ -209,7 +214,7 @@ All common code (and shared components) supposed to be in `common/`.
 ### Javascript / Javascript-React
 
 - ESLint is used as linter and prettier as formatter. Both are configured as devDependencies to
-  enforce default eslint configuration eventually overidden by
+  enforce default eslint configuration eventually overridden by
   [airbnb rules](https://airbnb.io/javascript/) translation. A few rules (see eslintrc) has
   been disabled and will be re-enabled in the near future):
   - 'no-named-as-default': 'off',