Once in a while you'll have a topic that actually could fit in 3 or 4 categories.
You also want all the answers going into just one topic instead of spread over all those categories.
When you have a topic which would fit in 2 categories, that is no problem, it can be solved with a shadow link to the original topic in the best fit categorie, but as soon as there are 3 or more categories that would fit and you still want to let all the answers go into the main, you'll have to make fake shadow topics and alter those with phpMyAdmin manually later.
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Same thing goes when you want the shadow link to be sticky, you'll have to go into phpMyAdmin to make that happen
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Is it not possible to make an extension for this ?
Advanced Shadow which makes it posible to do all this without going into phpMyAdmin and later maybe even gets connected to the user rights so the moderators for example can use it too
Using shadow topics as a kind of 'shortcuts' so to speak.