As they paraded through a Bangkok shopping mall in crop tops to mock Thailand's king, protesters made an incongruous sight among the festive decorations.

They brought stares, smiles and some muted cheers, but the few dozen activists were far short of the tens of thousands who joined earlier anti-government protests that broke the taboo on criticizing King Maha Vajiralongkorn.

After months of street demonstrations that have shaken Thailand's establishment, the best-known figures of a movement that drew tactics and inspiration from protests in Hong Kong said they are at a critical juncture.