Reproduction steps:
1. Open the attached project “ReproProject”
2. Open the scene “Main”
3. Enter Play Mode
4. In the Game view, press File → <Redacted> (see internal comments)
5. Observe the result in the Game view and the Console window

Actual result: Error appears in the Console window: InvalidProgramException: Invalid IL code in <user_namespace> (): IL_007a: brtrue.s IL_0093 <Redacted> UI menu is not opened
Expected result: <Redacted> UI menu opens, no errors in the Console Window

Reproducible in: 6000.3.12f1, 6000.4.1f1
Could not test with: 6000.0.71f1, 6000.5.0ab1, 6000.6.0a1 (unsolvable package compilation errors)

Reproducible on: Windows 11
Not reproducible on: No other environments tested

Note: The code which causes the error is located at file <Redacted2> at lines 59 and 70