anchor.diff:  
   (export-always 'find-suggestions)
   (defun find-suggestions (string)
  -  (gethash (alex:symbolicate (string-upcase string)) +migration-suggestions+))
  +  (alex:when-let ((sym (ignore-errors (uiop:safe-read-from-string string))))
  +    (gethash (symbol-name sym) +migration-suggestions+)))
   
   (defmacro define-migration (major-version-string &body body)
     (let ((result '()))
  
positive.code: (in-package :nyxt/migration)
  
  (defparameter +migration-suggestions+ (sera:dict)
    "Map between symbols and `suggestion's.")
  
  (define-class suggestion ()
    ((symbols
  
negative.code: 
  (defmethod initialize-instance :after ((suggestion suggestion) &key)
    (dolist (sym (symbols suggestion))
      (when (gethash (symbol-name sym) +migration-suggestions+)
        (alex:deletef (gethash (symbol-name sym) +migration-suggestions+)
                      suggestion
                      :test #'suggestion=))
      (push suggestion (gethash (symbol-name sym) +migration-suggestions+))))
  
  (defun version-suggestions (major-version)
    (let ((result '()))
  