Cross-posting the same caption everywhere puts the same URL in five places where it behaves five different ways. Nothing errors. It just does nothing on some of them.
Network by network
- Instagram — a URL in a caption is plain text. It is not clickable and cannot be copied easily. It works in the bio, and in a story link sticker.
- Facebook — links work normally and get a preview card. This is the one network where the old instincts still apply.
- Threads — links in a post are clickable. Whether they are rewarded is a different question, and there is no honest reading of it from outside.
- TikTok — no clickable links in a caption. The bio link is the route, and for most accounts that is the only one.
- Telegram — links work fully, get a preview, and nothing penalises them. It is the friendliest network for anything you actually want people to open.
The pattern underneath
Networks that sell attention are reluctant to hand it away, and networks that do not, are not. Telegram has no feed algorithm to protect, so a link is simply a link. That is the whole explanation, and it predicts the behaviour better than any list of tips.
If a link is the point of the post, ask which network you are actually posting for — and let the others carry a version that does not need one.
What to do instead of the same caption
Strip the URL from the Instagram and TikTok versions and say where to find it instead. Keep it in the Facebook and Telegram versions where it earns its place. Three seconds of editing, and the posts stop looking like they were pasted.
A bio link that changes with every post is worse than a stable one people learn. If it moves constantly, nobody builds the habit of looking.