Repository: opencv
Issue: Errant unhandledRejection handler in opencv.js causes Node process to crash on problems extraneous to the lib itself
Labels: category: javascript (js)

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##### System information (version)
<!-- Example
- OpenCV => 4.5.5
- Operating System / Platform => mac m1
- Compiler => N/A
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- OpenCV => 4.5.5
- Operating System / Platform => mac m1
- Compiler => N/A (opencv.js)

##### Detailed description

I'm using the prebuilt opencv.js files, and noticed that there is a `process.on('unhandledRejection')` call which causes the node process to exit (in the implementation of `abort`) in the case of *any* unhandled rejection, even ones unrelated to the workings of this library.

This is not super desirable since it may conflict with containing apps' rejection policies. It seems unnecessary as well. Is there a reason it's in place? As far as I can tell the library doesn't even really use Promises.

##### Steps to reproduce

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