I want to be able to display more thumbnails at a time in the thumbnail pane, particularly when it has been resized to show multiple columns. Is there a way to specify less space between the thumbnails?
Also, I noticed that the resize handle for the thumbnail pane is only visible when the WebViewer is greater than a certain width. Is it possible to make sure it’s always visible?
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To change the spacing between thumbnails, you could use one of two approaches:
1 - Add a CSS file on top of the native CSS using the WebViewer instance option css (https://www.pdftron.com/api/web/global.html#WebViewerOptions__anchor)
2 - Fork and customize the UI and change the behavior and appearance in any way you want. The entry point would be this file: https://github.com/PDFTron/webviewer-ui/blob/8.4/src/components/ThumbnailsPanel/ThumbnailsPanel.js. Here is more information on how to do that: https://www.pdftron.com/documentation/web/guides/advanced-customization/#forking-and-linking
Regarding the second question: WebViewer UI uses redux store values to determine if the resize bar should be added to the page or not. The only way to change that would be to fork and customize the UI, specifically this file and line: https://github.com/PDFTron/webviewer-ui/blob/e1606141b75caec0f589205e186dedef4b238608/src/components/LeftPanel/LeftPanel.js#L149