One thing I’ve found in my lifetime when changing themes for a website, it can seriously screw up the Search Engine Rank Positions of any website. I have changed the themes of one of my old forum that has shut down sadly. Not because of changing themes but for the fact that I had no time to manage more than one forum at that time and I had a tight schedule as well.
But if you absolutely want to change your site’s theme but don’t want to go down in SERPs, here is a trick. While changing themes, slowly get more and more backlinks for your new theme keywords. Keep the old ones because they may bring in some traffic even if it will get untargetted at times but it will all convert at a point. But take my advice, if you want a new theme for your site and if it is completely different from the current one, don’t do it, just make another website and be over with it.
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