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Hi, I would add other descriptive alt tags. Keep in mind that alt tags are also displayed when your image doesn't load for one reason or another. In your case, i wouldn't stuff these with keywords as you are in a commercial branche. I would keep the keyword alts for the main image. I also noted that your image filenames arent optimized (on the Edelweiss chalet) - i would consider renaming them first before you worry about thumbnail alts. You could consider naming the chalet "Zell-am-see-Oostenrijk-Chalet-Edelweiss.jpg" for example. Hope this is useful

If the content is the same, but translated, without the hreflang tag, it is duplicate content. The hreflang tag is there to serve as a signal that you know the content is the same but translated and you want Google to know that as well. This situation is exactly what hreflang is made for.

Hi James, Thanks for your respons.i checked a few pages and I don't see a schema markup on our website for twitter? where did you found them? generally, will this solve the issue? or do you see some other points to improve? is it an idee to remove the schema markup and use the data highlighter? Kind regards, Jeroen