Gallery images are not displayed large

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When i click on a Gallery image on the model screen, it moves to a single image screen and enlarges it, but even though the image size is larger than the window size, it is displayed at a smaller size.Pressing the i button does not change anything. It doesn't change even if I reload the browser.

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However, if I resize the browser window, the image size fits the window size.

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Images should fit the window size from the beginning, without having to resize the browser window. (This is of course different if the image size is smaller than the window size)