"Schopenhauer expressed his dislike for the philosophy of his contemporary Georg Wilhelm Friedrich Hegel many times in his published works. The following quotation is typical:
'If I were to say that the so-called philosophy of this fellow Hegel is a colossal piece of mystification which will yet provide posterity with an inexhaustible theme for laughter at our times, that it is a pseudo-philosophy paralyzing all mental powers, stifling all real thinking, and, by the most outrageous misuse of language, putting in its place the hollowest, most senseless, thoughtless, and, as is confirmed by its success, most stupefying verbiage, I should be quite right.
Further, if I were to say that this summus philosophus [..] scribbled nonsense quite unlike any mortal before him, so that whoever could read his most eulogized work, the so-called Phenomenology of the Mind, without feeling as if he were in a madhouse, would qualify as an inmate for Bedlam, I should be no less right.'
In his Foreword to the first edition of his work Die beiden Grundprobleme der Ethik, Schopenhauer suggested that he had shown Hegel to have fallen prey to the Post hoc ergo propter hoc fallacy.
Schopenhauer thought that Hegel used deliberately impressive but ultimately vacuous verbiage. He suggested his works were filled with “castles of abstraction” that sounded impressive but ultimately had no content. He also thought that his glorification of church and state were designed for personal advantage and had little to do with the search for philosophical truth. For instance, the Right Hegelians interpreted Hegel as viewing the Prussian state of his day as perfect and the goal of all history up until then."
--- Works of Arthur Schopenhauer: The Wisdom of Life, Religion: a Dialogue, On Human Nature, The Art of Literature, The Art of Controversy, On Authorship and Style and Other Essays (Mobi Collected Works)
Someone: Hegel is infamous for his incomprehensible jibberish; it's not any better in the German original...