Is it considered academic dishonesty and plagiarism for a researcher during their PhD to alter (by adding or omitting) the footnotes of texts they quoted for their research?

Quoting is the نقل (transference) of one or more sentences from another source as they are, without alteration. The condition for its permissibility is that the transference be done faithfully, attributing the quote to its author. As for transferring from others' works without referencing the sources, it is considered academic theft and falls under the category of "one who is satiated with what he has not been given is like one who wears two garments of falsehood." If accuracy and academic integrity are observed by attributing the effort to its owner and declaring the source, and clarifying what has been added or modified, then there is no harm in it. This is a legitimate utilization that has not been denied throughout Islamic history.