Fix math not being read in Chromium-based browsers (#17421) (#17548)

Fixes #17421

Summary of the issue:
Chromium-browsers were changed to return E_NOTIMPL and broke speech and braille of all math equations (i.e., no speech or braille for math) in those browsers because NVDA passes along a 'not implemented' COM exception.

Description of user facing changes
This restores the behavior of NVDA (i.e., math reads) as before the change.

Description of development approach
A try/except block is added around the call. If the error is E_NOTIMPL, the code moves on as before. Otherwise, the error is re-raised as before.

source/NVDAObjects/IAccessible/ia2Web.py

@@ -12,6 +12,7 @@
 )
 from ctypes import c_short
 from comtypes import COMError, BSTR
+from comtypes.hresult import E_NOTIMPL
 
 import oleacc
 from annotation import (
@@ -334,7 +335,13 @@ def _get_mathMl(self):
 			# Try the data-mathml attribute.
 			attrNames = (BSTR * 1)("data-mathml")
 			namespaceIds = (c_short * 1)(0)
-			attr = node.attributesForNames(1, attrNames, namespaceIds)
+			try:
+				attr = node.attributesForNames(1, attrNames, namespaceIds)
+			except COMError as e:
+				if e.hresult != E_NOTIMPL:
+					log.debugWarning(f"MathML getting attr error: {e}")
+					raise
+				attr = None
 			if attr:
 				import mathPres
 

user_docs/en/changes.md

@@ -2,8 +2,11 @@
 
 ## 2024.4.2
 
-### Bug Fixes
+This is a patch release to fix bugs with braille devices and reading math in Chromium.
+
+### Bug fixes
 
+* Fixed bug with with reading math in Chromium Browsers (Chrome, Edge). (#17421, @NSoiffer)
 * Humanware Brailliant BI 40X devices running firmware version 2.4 now work as expected. (#17518, @bramd)
 
 ## 2024.4.1