Fix font matching style bug (#2503)

novelwriter/common.py

@@ -445,6 +445,7 @@ def fontMatcher(font: QFont) -> QFont:
     default Qt font matching algorithm doesn't handle well changing
     application fonts at runtime.
     """
+    font.setStyleName(None)  # Make sure no font style name is set from config, see #2502
     info = QFontInfo(font)
     if (famRequest := font.family()) != (famActual := info.family()):
         logger.warning("Font mismatch: Requested '%s', but got '%s'", famRequest, famActual)

tests/test_base/test_base_common.py

@@ -537,6 +537,11 @@ def testBaseCommon_fontMatcher(monkeypatch):
     nonsense = QFont("nonesense", 10)
     assert fontMatcher(nonsense) is nonsense
 
+    # Style is reset
+    nonsense.setStyleName("blabla")
+    assert nonsense.styleName() == "blabla"
+    assert fontMatcher(nonsense).styleName() == ""
+
     # General font
     if len(QFontDatabase.families()) > 1:
         fontOne = QFont(QFontDatabase.families()[0])