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Fixed in 2020.2.X

Fixed in 2019.4.X, 2020.1.X



Found in





Issue ID




[WebGL] Async Tasks do not run on WebGL when Threading is enabled



Reproduction steps:
1. Open the attached project ("")
2. Open the repro scene ("SampleScene")
3. Enter Play Mode
4. Notice the logs about async tasks being printed out to the screen
5. Exit Play Mode and make a WebGL build
6. Run the build and inspect the printed messages on the screen

Expected result: Async task messages are printed to the screen
Actual result: Only 'Start' and 'End' messages are printed to the screen (async tasks doesn't run)

Reproducible with: 2019.3.14f1, 2020.1.0b9, 2020.2.0a11
Couldn't test with 2018.4 (errors when building the project)

Tested with: Chrome (81.0.4044.138)

  1. Response avatar

    Resolution Note (fix version 2020.2):

    IL2CPP wasn't generating the correct threaded code when threadingSupport flag was set in the project settings. Fixed in 2020.2.0a16

  2. Response avatar

    Resolution Note (fix version 2020.1):

    Fixed in 2020.1.0b17.4177

  3. Response avatar

    Resolution Note (fix version 2019.4):

    Fixed in - 2019.4.7f1

Comments (2)

  1. Af612385a6910fb9d89c5e6a957128db?d=mm


    Feb 22, 2021 19:33

    Why is this closed, doesn't work in 2019.4.8f1 either.

  2. Aa4c3234fcecf5dc7e931e416d886a82?d=mm


    Jan 13, 2021 12:31

    Just tested in 2019.4.7f1, it does not work.
    Simple thing like this does not work:

    Test.text = "1";
    await Task.Delay(1000);
    Test.text += "2";
    await Task.Delay(1000);
    Test.text += "3";

    Unity only pretends it's multi-platform, it's actually multi-pain.

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