Noticeable delay each time in-product release notes editor is made active.

[gregvanl]

• VSCode Version:1.6.0 insiders
• OS Version: Windows

Steps to Reproduce:

1. Follow test plan to enable in product release notes in insiders Test: Release notes in the product #12520
2. Help > Release Notes
3. Note delay (~1.5 seconds) when page is initially displayed.
4. Switch to a different editor and then go back to release notes.

The release notes editor is re-rendered and there is the same delay each time.
We should look into caching the rendered page since release notes are unlikely to change during the user's reading of the release notes. We don't need to cache release notes across sessions so the user will pick up any release note changes when they first open them (Help > Release Notes).

[gregvanl]

On my home wifi this can take up to 5 seconds (depending on what the kids are streaming).

[olingern]

I'm interested in helping out with this. A couple of questions for @joaomoreno @Tyriar

Idea:
Place a hook inside of loadReleaseNotes in src/vs/workbench/electron-browser/update.ts to see if a cached markup file exists, if it does load it instead of retrieving from https://code.visualstudio.com. Otherwise, load from url and write markup response to disk.

1. Frequency of caching: Are release notes final, or do they often update without regards to a release?
2. Location of file: I'm newer to the directory structure and thought out/vs/workbench/electron-browser/cache/release-notes.md may be a good place.

[joaomoreno]

@olingern You shouldn't write them to disk, but just keep them in memory. It's OK if they take up time loading once Code restarts.

[olingern]

@joaomoreno This one is a bit tricky as it doesn't seem I can test through the development build. Do you have any pointers for creating a build where I can see a full list of menu items?

[joaomoreno]

Yeah, you have to add to the top level product.json the following key:

    "releaseNotesUrl": "https://go.microsoft.com/fwlink/?LinkId=724002"

[olingern]

@joaomoreno Thanks!

I have a PR open, #15050, with a working fix, but a couple of issues:

• linting
  The gulp hygiene task is telling me my file ( and all files ) aren't formatted. I saw a couple of other issues in the repo chatting about this. I installed typescript-formatter and ran tsfmt -r update.ts, but it produced an error

Running gulp hygiene tells me all files in my project aren't formatted as well:

- Tests

It wasn't clear to me where tests for this feature would live. Based upon where other tests live, it looks like src/vs/workbench/test/electron-browser/update.ts is where this should live, but the electron-browser test directory doesn't exist, at the moment.

[mjbvz]

I believe this was fixed by #15050