WebGL: INVALID_OPERATION: texSubImage2D: no texture bound to target when running multiple networks together

[alessandrolenzi]

When i try to run multiple networks at once with WebGL, sometimes (it seems to depend on the network) the warning mentioned in the title appears. Moreover the result of the computation is made entirely of zeroes.

I was able to extract a minimal, verifiable and complete example to reproduce the issue, that you can find in index.html, contained in the attached zip file. The file also contains a network with which the problem arises.

test_network.zip

To run the example, just start a web server, navigate to a webpage containing the code above and run from the console the following:
let res = await test(<address_of_the_network>, <number_of_parallel_numbers>, <link_to_an_image>)
I can reproduce the issue with a number of parallel numbers greather or equal to two.
Is there any way to fix this problem?

Thanks