Possible Clues:

• Internet abbreviation before an internet abbreviation?
• Abbr. before a lengthy post's summary
• Abbr. before a synopsis
• 'Here's a brief summary,' in internet-speak
• "I lost interest" acronym spelled out by the starts of four answers in this puzzle
• 'Here's a quick summary,' in internet-speak
• Short response to a lengthy online post
• "Here's the one-sentence version" letters
• 'Here's a summary' initials
• "No time to wade through this" initialism