This quote-skipping should be done at the level of individual message parts, not when processing the unified contents. As it is, if a mail contains two inline text/plain parts, then the answer to "shall we include the second one as a quotation" depends on whether the first one has a signature (actually, a signature separator).
Dear Bug Submitter, This bug has been stagnant for a long time. Could you help us out and re-test if the bug is valid in the latest version? I am setting the status to NEEDSINFO pending your response, please change the Status back to REPORTED when you respond. Thank you for helping us make KDE software even better for everyone!
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