If you have recommender enabled for a size chart, by default, the app will also inject a "what's my size" link, which will open the recommender tab directly. The link also changes content depending on when a recommendation is made. As you can see in the following screenshot, there are three states of the button.
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If you wish to remove this, go to settings and click on the "Recommender" tab.
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Then, in the sizing injection selector, you can select the injection as "Do not inject".
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