Reproduction steps:
1. Create a new 3D project
2. Open the "Assets/Scebnes/SampleScene.unity" Scene
3. Import the "Capriola-Regular.ttf" and "NotoSansKR-Regular.ttf" fonts into the "Assets" folder
4. Press the right mouse button on the "Assets/Capriola-Regular.ttf" font and select "Create -> TextMeshPro -> Font Asset" (do the same for the "Assets/NotoSansKr-Regular.ttf" font)
5. In the Hierarchy, press the right mouse button on an empty space and select "UI -> Canvas"
6. In the Hierarchy, press the right mouse button on the "Canvas" GameObject and select "UI -> Image"
7. In the Inspector of the "Canvas" GameObject, press the "Add Component" button, then input "Mask" and select it
8. In the Hierarchy, press the right mouse button on the "Image" GameObject and select "UI -> Text - TextMeshPro"
9. In the Inspector of the "Text (TMP)" GameObject, in the "TextMeshPro - Text (UI)" Component text field, input "Hello 안녕하세요"
10. Change the "Font Asset" parameter to "Capriola-Regular SDF.asset" font asset
11. Change the "Vertex Color" parameter to black
12. Expand the "Extra Settings" and uncheck the "Maskable" parameter
13. Adjust the position of the text in the "Rect Transform" Component so that half of the Korean word would be outside of the white box
14. In the Project window, select the "Capriola-Regular SDF.asset"
15. In the Inspector, scroll down until you see the "Fallback Font Assets" section and press '+' to add an empty parameter slot
16. Drag the "NotoSansKR-Regular SDF.asset" from the Project window to the parameter slot
17. Open the Game view

Alternative reproduction steps:
1. Open the attached “repro_IN-84806“ project
2. Open the “Assets/Test.unity“ Scene
3. Open the Game view

Expected result: All text, including the Korean characters, are visible and ignores the parent mask
Actual result: ASCII characters are visible and ignore the mask, but the Korean characters are cut off by the mask boundaries

Reproducible with: 2021.3.44f1, 2022.3.49f1, 6000.0.22f1

Reproducible on: Windows 10 (22H2), Windows 11 (10.0.22631) (user's)
Not reproducible on: No other environments tested

Notes:

* Reproducible in Player
* “Capriola“ font can be downloaded here: [https://fonts.google.com/specimen/Capriola|https://fonts.google.com/specimen/Capriola|smart-link]
* “NotoSansKR“ font can be downloaded here: [https://fonts.google.com/noto/specimen/Noto+Sans+KR|https://fonts.google.com/noto/specimen/Noto+Sans+KR|smart-link]