Flow variable changes when it shouldn't

Hi Developers,

As you'll notice in the code below, I'm only using the flow.get method, I'm not using the set method anywhere.
Unfortunately, despite entering anything into the text node, my flow variable in memory also changes.
This is only a piece of larger code but in no way connected to the set node.
Is it possible for permanent connections between variables to be created in memory?

If this is my misunderstanding how the flow variable works, I am asking you to explain the topic, because a similar situation is repeated to me once again.

Thank you very much in advance,

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Discussed here: Changes to Context Flow Variable also changes source array it was extracted from

In short, the pass-by-reference nature of JavaScript means you have to be careful with this sort of thing, and explicitly clone objects if you don't want them being modified.

Thanks @knolleary, for so quick response.

I dive into reading.