"Welcome to Twitter Mr Western Puppet," one comment to Ahmad al-Jarba read. Others called him a Saudi stooge and scorned the opposition's perceived ineffectiveness.
The comments reflect the deep disillusionment and distrust that many Syrians have come to feel toward the Syrian National Coalition, Syria's main opposition group in exile.
They also underline the predicament of who will represent the Syrian opposition at an upcoming peace conference in Geneva marking the first face-to-face meeting between Syria's warring sides.
"Each of them represents himself and maybe his wife," said an anti-government activist in the central Homs province, who uses the pseudonym Abul Hoda. "Nobody here pays any attention to what they say."
More From This Section
The Syrian National Coalition is seen by many as a disparate group of out-of-touch exiles with inflated egos and non-Syrian allegiances.
Syrians often deride it as the "five-star-hotel opposition" for spending more time meeting in luxury hotels than being on the ground in Syria.
But groups known as the "internal opposition" are themselves seen as aging and submissive to Assad's government, incapable of playing an effective opposition role for fear of arrest.
More importantly, the rebel factions that hold the real power on the ground won't go to Geneva. Some of the most powerful Islamic brigades have distanced themselves from the coalition.
Meanwhile, rebels are losing ground to a crushing government military offencive.