Meaning:
“发” means “to give out,” and “糖” means “candies.” As traditionally newly-weds in China would give out candies to their acquaintances as a token to celebrate their marriage, Chinese netizens use the term to refer to the scenario where their favorite celebrity couples publicly display affection, either in real life or on social media. The term is also used when fictional couples in movies, TV shows or animations display affection. Fans even call some romcoms “发糖剧” (literally, candy-giving shows) because the plotlines are syrupy.
Example:
A: 一大早又在刷手机。
Yīdàzǎo yòu zài shuāshǒujī。
You are playing with your phone again. Isn’t it too early?
B: 我喜欢的小哥哥又发糖了呢。
Wǒ xǐhuan de xiǎogēgē yòu fātáng le ne。
The young actor I am so fond of has just posted a very sweet message about his girlfriend.