MISC: Game crashes when loading via file://

[catloversg]

Bitburner is a web application. A player can play it via:

• Online web version (https://bitburner-official.github.io/ and https://bitburner-official.github.io/bitburner-src/). [1]
• Electron version (Steam app). [2]
• Web version: Download a zip file, unzip it, then open index.html. [3]

[1] and [2] are the easiest ways to play this game, while [3] is only useful in some very special cases. After #1216 is merged, the game crashes when loading via file://. To enable TS and JSX support, we use swc-wasm, so we have to load a WASM file. However, WASM files cannot be loaded via file:// due to the same-origin policy.

Technically, I can refactor the codebase to make TS/JSX support optional and disable it when the game cannot load the required WASM file. However, I think it's not worth the effort. The refactoring will be complicated, and [3] is not a usual way to play our game. If a player (or contributor) needs to open the game in this way, they can use these workarounds:

• Firefox: Set security.fileuri.strict_origin_policy in about:config page to true.
• Chrome: Open Chrome with --allow-file-access-from-files.

Note that these workarounds have their own problems:

• They change the security setting of the browser. Proceed at your own risk.
• There is no guarantee that they will work in the future. In the past, Firefox used privacy.file_unique_origin. The new setting security.fileuri.strict_origin_policy may also be removed or changed in the future.

I created this issue as documentation for this new behavior change. If there are reports about this problem, we can link this issue.

@Snarling @d0sboots @gmcew FYI.

[d0sboots]

Why is this not a problem for [2]? I'm guessing it's because of Electron's custom request handler, where we allow file:// access to the game's local resources, but lock it down otherwise.

Going forward, if we want to support [3] that may need to be the answer: start distributing the electron build instead of just the web files. File:// access is incredibly restricted (for good reasons), making it very hard to use any modern webpage without a server.

[catloversg]

You are right. Our custom request handler handles file:// requests, so the Electron app does not have this problem.