Freewall encompasses two variations of Masonry-style layout. In a masonry layout, thumbnail cells need not be the same height; images will rearrange themselves to close unused space, like stones laid into a wall.
To use these layouts, under the Appearance pane, set Grid-type :desktop as “Freewall (Masonry)”:
For Layout, select either “Masonry, Elastic” or “Masonry, Rigid”:
Thumbnails expand, contract and reflow to best fill the full-width of the gallery container.
Thumbnails maintain their size while the number of columns adapts to the viewport width.
Customization options will vary slightly between the two layouts, though to a minimal degree. If you want to frame your thumbnails with thick borders, then use the Rigid layout.
For best results, set your Thumbnail Height huge, then use the Thumbnail Width slider to constrain your thumbnails' size:
If the thumbnails do not update size in Lightroom's preview, you can force the Web module to re-render the images by toggling Watermarks on and then off again, or vice versa.
The Turning Gate
Creating webbly, wobbly, Lightroomy things since 2007.