Customer editor extension fails to read 50MB+ file

[svew]

VSCode info:

Version: 1.61.0 (user setup)
Commit: ee8c7def80afc00dd6e593ef12f37756d8f504ea
Date: 2021-10-07T18:13:09.652Z
Electron: 13.5.1
Chrome: 91.0.4472.164
Node.js: 14.16.0
V8: 9.1.269.39-electron.0
OS: Windows_NT x64 10.0.19043

I've been developing a customer editor extension to display log files. When trying to open very large files (50MB+) using my extension, I get the following error:

ERR Unable to retrieve document from URI 'file:///c%3A/Users/wasvendd/Downloads/XTS_Downloads/AlwaysOnMonitor_2.log': Error: Unable to retrieve document from URI 'file:///c%3A/Users/wasvendd/Downloads/XTS_Downloads/AlwaysOnMonitor_2.log'
	at k.getDocument (c:\Users\wasvendd\AppData\Local\Programs\Microsoft VS Code\resources\app\out\vs\workbench\services\extensions\node\extensionHostProcess.js:94:150899)
	at I.$resolveWebviewEditor (c:\Users\wasvendd\AppData\Local\Programs\Microsoft VS Code\resources\app\out\vs\workbench\services\extensions\node\extensionHostProcess.js:95:78673)
	at i._doInvokeHandler (c:\Users\wasvendd\AppData\Local\Programs\Microsoft VS Code\resources\app\out\vs\workbench\services\extensions\node\extensionHostProcess.js:98:13802)
	at i._invokeHandler (c:\Users\wasvendd\AppData\Local\Programs\Microsoft VS Code\resources\app\out\vs\workbench\services\extensions\node\extensionHostProcess.js:98:13486)
	at i._receiveRequest (c:\Users\wasvendd\AppData\Local\Programs\Microsoft VS Code\resources\app\out\vs\workbench\services\extensions\node\extensionHostProcess.js:98:12097)
	at i._receiveOneMessage (c:\Users\wasvendd\AppData\Local\Programs\Microsoft VS Code\resources\app\out\vs\workbench\services\extensions\node\extensionHostProcess.js:98:10826)
	at c:\Users\wasvendd\AppData\Local\Programs\Microsoft VS Code\resources\app\out\vs\workbench\services\extensions\node\extensionHostProcess.js:98:8922
	at a.fire (c:\Users\wasvendd\AppData\Local\Programs\Microsoft VS Code\resources\app\out\vs\workbench\services\extensions\node\extensionHostProcess.js:66:1712)
	at l.fire (c:\Users\wasvendd\AppData\Local\Programs\Microsoft VS Code\resources\app\out\vs\workbench\services\extensions\node\extensionHostProcess.js:74:15990)
	at c:\Users\wasvendd\AppData\Local\Programs\Microsoft VS Code\resources\app\out\vs\workbench\services\extensions\node\extensionHostProcess.js:113:30514
	at a.fire (c:\Users\wasvendd\AppData\Local\Programs\Microsoft VS Code\resources\app\out\vs\workbench\services\extensions\node\extensionHostProcess.js:66:1712)
	at l.fire (c:\Users\wasvendd\AppData\Local\Programs\Microsoft VS Code\resources\app\out\vs\workbench\services\extensions\node\extensionHostProcess.js:74:15990)
	at u._receiveMessage (c:\Users\wasvendd\AppData\Local\Programs\Microsoft VS Code\resources\app\out\vs\workbench\services\extensions\node\extensionHostProcess.js:74:21260)
	at c:\Users\wasvendd\AppData\Local\Programs\Microsoft VS Code\resources\app\out\vs\workbench\services\extensions\node\extensionHostProcess.js:74:18138
	at a.fire (c:\Users\wasvendd\AppData\Local\Programs\Microsoft VS Code\resources\app\out\vs\workbench\services\extensions\node\extensionHostProcess.js:66:1712)
	at v.acceptChunk (c:\Users\wasvendd\AppData\Local\Programs\Microsoft VS Code\resources\app\out\vs\workbench\services\extensions\node\extensionHostProcess.js:74:13351)
	at c:\Users\wasvendd\AppData\Local\Programs\Microsoft VS Code\resources\app\out\vs\workbench\services\extensions\node\extensionHostProcess.js:74:12699
	at Socket.w (c:\Users\wasvendd\AppData\Local\Programs\Microsoft VS Code\resources\app\out\vs\workbench\services\extensions\node\extensionHostProcess.js:113:13465)
	at Socket.emit (events.js:315:20)
	at addChunk (internal/streams/readable.js:309:12)
	at readableAddChunk (internal/streams/readable.js:284:9)
	at Socket.push (internal/streams/readable.js:223:10)
	at Pipe.onStreamRead (internal/stream_base_commons.js:188:23)
	at Pipe.callbackTrampoline (internal/async_hooks.js:131:14)
log.ts:301   ERR Error: Assertion Failed: argument is undefined or null
    at m (types.ts:100)
    at Ii.resolve (customEditorInput.ts:304)
    at processTicksAndRejections (internal/process/task_queues.js:93)
    at async ta.setInput (webviewEditor.ts:137)
    at async h.doSetInput (editorPanes.ts:264)
    at async h.doOpenEditor (editorPanes.ts:142)
    at async h.openEditor (editorPanes.ts:110)
    at async editorGroupView.ts:1061
    at async explorerView.ts:445
notificationsAlerts.ts:42 Unable to open 'AlwaysOnMonitor_2.log': Assertion Failed: argument is undefined or null.
onDidChangeNotification @ notificationsAlerts.ts:42

Any reasons for this to happen? Thanks

[svew]

Closing myself due to question being answered by #31078