I recently upgraded lsp-mode in emacs, and it appears there's a new setting, lsp-ui-sideline-actions-kind-regex, which defaults to showing only quickfix and refactor-type assists. There are several bug-removal assists that rust-analyzer offers that present as the "" type, including adding missing imports. The lsp-mode issue&work-around for this is emacs-lsp/lsp-ui#455
My intuition is that rust-analyzer is not sending the correct type for those assists & that they should be quickfixes; do you agree?