Under the hood: How variations are created
Personalizations are like an additional layer of information that is sent to your website visitors. This layer consists of so-called keys. Keys are hashed content that gets injected into your variations. When you edit a variation, you either create or change keys.
You could think of keys as new content replacing the old.
Once someone visits your page, Unless sends out the original page and places variation-specific keys on top of it. A key basically replaces the original content. That is what makes the system so lightweight - a variation is not a "new" page, it's just a layer. As you can imagine, this layer can be affected by changes you make to the original page.
How Unless handles changes to the original page
Unless operates right on top of your website. If you adjust the original page, Unless will pick up on that and implement the changes on all associated variations. We do this because we work under the assumption that you as the website owner want to overrule personalizations.
This way, you only have to make changes once. However, this process can cause unwanted changes, so whenever you edit your original page, keep in mind how it will affect your variations.
Let's say the headline of your original page is "Unique Bouquets for Mother's Day". Next, you create an Unless variation and change the headline to "Buy a gift for Mother's Days". So far, everything will work smoothly.
However, your colleague decides to change the headline of your original page to "Classic Bouquets for Mother's Day".
Now, the following happens: The original headline "Unique Bouquets for Mother's Day" got deleted when your colleague changed the page. So, Unless "lost" the information about where to put the headline "Buy a gift for Mother's Days". As a consequence, your variation will now display the headline your colleague chose. He basically overwrote the key.
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