Is there more empty between lines than lines with text?
Perhaps a reduction in magnification helps to make some text appear, or perhaps the text is "invisible" with some "secret" writing to hide information:
It could also be the lack of support for the versions of the technologies used, a periodic situation in an era of totalitarianism in information technology, but more likely:
The natural and normal ignorance of not being informed about a subject.
Main languages used: Portuguese, English.
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