Hello Bagus, yes this is important and this is work in progress, see https://github.com/aaFn/Bookmark-search-plus-2/issues/29 and https://github.com/aaFn/Bookmark-search-plus-2/issues/181

This is a multi-steps work in the code, and I do not have a lot of time currently, but coming soon now.

Thanks, aaFn.
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Hello @Bagus, you will be happy to see that now multi-selection is available, as of 2.0.103 :-)