bug(web): error displayed when typing with korean_rr keyboard in Keyman for iOS or Keyman for Android

[ermshiperete]

The Korean RR keyboard can show can show an IME window at the bottom of the OSK for selecting Hanja characters. When clicking one of the displayed options the keyboard switches (to the next/first keyboard in the list of available keyboards) and an error popyp is displayed.

When using the Korean RR keyboard while not in the Keyman app no error is displayed, but the keyboard switch still happens.

screen-20260626-175138.mp4

Keyman 18.0.249
Android 16

Also happening with Keyman 19

[mcdurdin]

Call stack:

Uncaught TypeError: KeymanWeb.GetLastActiveElement is not a function
Keyboard_korean_rr.insertCallback	@	korean_rr.js:387
Keyboard_korean_rr.clickCallback	@	korean_rr.js:354
e.onclick	@	korean_rr.js:322

[mcdurdin]

Some analysis - it's a bit of a mess:

1. There are two inconsistent implementations:
   • browser/keyboardInterface.ts defines getLastActiveElement(): AbstractElementTextStore<any> and GetLastActiveElement (alias) (doc), accessible as KeymanWeb.GetLastActiveElement()/KeymanWeb.getLastActiveElement()
   • browser/keymanEngine.ts defines getLastActiveElement(): HTMLElement (doc), accessible as keyman.getLastActiveElement()
2. There is no equivalent implementation in webview/keymanEngine.ts or webview/keyboardInterface.ts (which does not exist).
3. There is no implementation in engine/keymanEngineBase.ts or engine/keyboardInterfaceBase.ts.
4. The browser implementation returns a TextStore but the documentation defines the return value as an element (i.e. HTMLElement).
5. browser ContextManager defines get lastActiveTextStore(): AbstractElementTextStore
6. The ui modules use keymanweb.getLastActiveElement() but this is an alias for keyman.getLastActiveElement() NOT KeymanWeb.getLastActiveElement() (We need to refactor that keymanweb variable out of those modules)

Keyboards such as korean_rr use the value returned from GetLastActiveElement() only to pass into functions such as KeymanWeb.KC(), which expects a TextStore, not a HTMLElement:

korean_rr/source/korean_ime.js:387-389:

    a = KeymanWeb.GetLastActiveElement();        
    KeymanWeb.KT(null);    /* KT will refocus the active element in the case of a mouse click */
    c = KeymanWeb.KC(12,12,a); 

I audited the use of KeymanWeb.GetLastActiveElement and KeymanWeb.getLastActiveElement in the keyboards repository. Its value is only ever used to pass back into KeymanWeb.KC, KeymanWeb.KO and related functions, so the TextStore type is appropriate.

Proposed actions:

1. KeyboardInterface.getLastActiveElement() appears to never have been used, deprecate

2. KeyboardInterface.GetLastActiveElement() should be marked deprecated

3. Introduce KeyboardInterface.getLastActiveTextStore()

4. Update documentation:

   • fix return type for KeymanWeb.GetLastActiveElement()
   • note the different return type for keyman.getLastActiveElement()
   • clarify that keyman.GetLastActiveElement() is only available in browser, not webview (so not in apps)
   • add docs for KeymanWeb.GetLastActiveTextStore()
   • note that KeymanWeb.GetLastActiveTextStore() is not deprecated but is the appropriate interface for keyboards to use.
   • Improve documentation about KeymanWeb vs keyman globals in the documentation: KeymanWeb is for use only by keyboards, keyman is for use by apps/websites (note that keyboards use keyman for some boilerplate to determine version of KeymanWeb; for stability reasons, this won't change). This exists but is buried in interface/index.md.
   • (Separate note on documentation: the index of the documentation needs to be reorganized to be enumerating the modules by module name, rather by module function, i.e.

   [KeymanWeb Core Module](core)
   :   The KeymanWeb core module is exposed to the developer as `window.keyman`.
   
   [On-Screen Keyboard Module](osk)
   :   The On-Screen Keyboard module is exposed to the developer as `window.keyman.osk`.
   

   should be something like:

   [`keyman`](core)
   :   The KeymanWeb core module (`window.keyman`)
   
   [`keyman.osk`](osk)
   :   On Screen Keyboard module
   

5. Update keyboards where possible to use KeymanWeb.getLastActiveTextStore() instead of KeymanWeb.GetLastActiveElement()

All of this also applies to KeymanWeb.FocusLastActiveElement().

[mcdurdin]

Secondary: the error message appear never to have been posted to Sentry?

Update: this arises because of use of file: protocol means the global onerror handler gets a generic 'Script Error', which is then filtered out by default by Sentry (Sentry blog)

My hope then, is that this will be improved by #16146 (and I'll go ahead and try that now!)

[sentry]

Sentry Issue: KEYMAN-WEB-XM

[mcdurdin]

Yes, as seen by the comment above, #16146 will make more errors visible to us in Keyman for Android, and the corresponding #16136 for iOS will do the same for Keyman for iOS.