We currently do not have e2e tests (i.e. "end-to-end" testing of whole scenarios how the user interacts with the app). This means to check if a change breaks existing functionally in other places, we currently click through the app ourselves which takes time and is unreliable. Instead, we should establish automated tests for this again which will also run in the CI of every PR.

• choose a e2e test framework
  • Playwright seems to gain traction, is supported by angular [>] and has a VS Code plugin to record tests easily [>]
  • Cypres might be an alternative
• set up the testing framework in our repository
  • i.e. install npm packages, etc.
• record some basic scenarios as samples
• discuss with core team and create a list of all the first / most relevant scenarios
• implement e2e tests for the first scenario
• enable e2e tests in CI pipelines #2309
• integrate e2e tests with Percy to add "visual regression testing" [>] (i.e. screenshot comparisons to highlight where the layout changes)

... then continue to gradually add e2e tests for all relevant scenarios: GoogleSheet