bug(web): blank keyboard after installing Keyman for Android or Keyman for iOS 19.0.242 or later

[ermshiperete]

I had Keyman 19 installed and properly working.

Then uninstalled it and installed Keyman 18 to test something.

Installed Keyman 19.0.245. Now all I get is a blank keyboard. Tried rebooting, re-installing keyboards, clearing data - nothing helped.

Uninstalled, installed Keyman 18 again - it's working there. Uninstalled, installed Keyman 19 again - blank keyboard.

[mcdurdin]

@jahorton I have reproduced this in 19.0.247-alpha. Current alpha builds are not working.

[mcdurdin]

Fetch API cannot load file:///data/user/0/com.tavultesoft.kmapro.debug/app_data/packages/sil_euro_latin/sil_euro_latin.js. URL scheme must be "http" or "https" for CORS request.

Uncaught (in promise) Error: Unable to download EuroLatin (SIL) Keyboard keyboard for English
    at _StubBasedErrorBuilder.keyboardDownloadError (keyboardLoadError.ts:96:12)
    at _DOMKeyboardLoader.<anonymous> (domKeyboardLoader.ts:41:26)
    at Generator.throw (<anonymous>)
    at rejected (keymanweb-webview.js:72:31)Caused by: TypeError: Failed to fetch
    at keyman-sentry.js:4520:30
    at _DOMKeyboardLoader.<anonymous> (domKeyboardLoader.ts:39:24)
    at Generator.next (<anonymous>)
    at keymanweb-webview.js:78:63
    at new Promise (<anonymous>)
    at __async (keymanweb-webview.js:62:12)
    at _DOMKeyboardLoader.loadKeyboardBlob (domKeyboardLoader.ts:32:110)
    at _DOMKeyboardLoader.<anonymous> (keyboardLoaderBase.ts:56:34)
    at Generator.next (<anonymous>)
    at keymanweb-webview.js:78:63
    at new Promise (<anonymous>)
    at __async (keymanweb-webview.js:62:12)
    at _DOMKeyboardLoader.loadKeyboardInternal (keyboardLoaderBase.ts:55:110)
    at _DOMKeyboardLoader.<anonymous> (keyboardLoaderBase.ts:46:17)
    at Generator.next (<anonymous>)
    at keymanweb-webview.js:78:63
    at new Promise (<anonymous>)
    at __async (keymanweb-webview.js:62:12)
    at _DOMKeyboardLoader.loadKeyboardFromStub (keyboardLoaderBase.ts:44:76)
    at _StubAndKeyboardCache.fetchKeyboard (stubAndKeyboardCache.ts:163:41)
    at _StubAndKeyboardCache.fetchKeyboardForStub (stubAndKeyboardCache.ts:122:17)
    at contextManagerBase.ts:368:52

loadKeyboardBlob now uses window.fetch() -- but fetch() does not support file: URIs (we run engine from file: on Android so we don't have to spin up a local http server). This is a regression from #12334. I think @ermshiperete can probably investigate; resolution may be to have a separate loader for Keyman Engine for Web when in the embedded contexts.

This is a problem for both iOS and Android. I have located Sentry reports for iOS but not for Android, which is a separate concern.