Translate the debug update email for development installs. Props Nao for initial patch. See #25667

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Themes page: Remove a z-index which caused the Current Theme overlay to overlay menu's, that otherwise appears unused. See #25948 

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Widgets: fix the placeholders dimensions so the sidebars don't jump when dragging a widget, see #25821
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Themes: Add a get_theme_update_available() function to retrieve an update link and use it on the Themes page. See #26078

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