Issue Type: Bug
So I have async yield function and when I call this function inside using await foreach all of the syntax highlighting goes away as it does not highlight keywords such as 'if' 'try' 'catch' or 'for'. Is this a known issue?

Extension version: 1.21.16
VS Code version: Code 1.43.2 (0ba0ca52957102ca3527cf479571617f0de6ed50, 2020-03-24T07:38:38.248Z)
OS version: Windows_NT x64 10.0.18363
System Info
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|---|---|
|CPUs|Intel(R) Core(TM) i7-1065G7 CPU @ 1.30GHz (8 x 1498)|
|GPU Status|2d_canvas: enabled
flash_3d: enabled
flash_stage3d: enabled
flash_stage3d_baseline: enabled
gpu_compositing: enabled
multiple_raster_threads: enabled_on
oop_rasterization: disabled_off
protected_video_decode: enabled
rasterization: enabled
skia_renderer: disabled_off_ok
video_decode: enabled
viz_display_compositor: enabled_on
viz_hit_test_surface_layer: disabled_off_ok
webgl: enabled
webgl2: enabled|
|Load (avg)|undefined|
|Memory (System)|15.60GB (7.56GB free)|
|Process Argv||
|Screen Reader|no|
|VM|0%|
@mshinnie Please try out the semantic highlighting in our 1.21.19-beta1 release.
@JoeRobich It works with version 1.21.19-beta and above.
Thanks a lot, it was driving me crazy!
this is fixed with semantic highlighitng
Most helpful comment
@mshinnie Please try out the semantic highlighting in our 1.21.19-beta1 release.