As you can see in the picture bellow there is an unexpected behavior of the trim() function, because is stripping the á
This code is part of javascript file that I've included in many projects without problems, but now a client of mine is facing this issue. The sad part is that i haven't access to the source code project client.
Trying your code in a regular browser show that it works as expected - jsfiddle.
Yes it is possible but it is considered a bad practice. I'll show how to do that because I think the code has it overridden already. Here is how to do it:
String.prototype.trim = x => console.log('trim override');
'olá'.trim(); // trim override
Unless it's run in an unexpected environment it is most likely that the original author has trim overridden to something that is different from native implementation. I would suggest you try to paste the polyfill with original implementation in to the console and checking if running it with that will fix the issue.
Here is the polyfill:
String.prototype.trim = function () {
return this.replace(/^[\s\uFEFF\xA0]+|[\s\uFEFF\xA0]+$/g, '');
};
console.log('olá'.trim());
If the output of this code gives you the correct result (not trimming á) you found the issue.