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Starting with the upcoming Q2 2026 release, the following legacy themes will no longer be supported for newly introduced controls:
- Expression Dark
- Windows 7
- Transparent
- Vista
- Summer
- Office Silver
- Office Blue
Note: This change applies only to newly introduced controls. Support for all of the existing ones (available before Q2 2026) that already use these themes will remain unchanged, and they will continue to function as before.