Fix missing replace inside next sibling

Author: wooorm

lib/index.js

@@ -136,7 +136,7 @@ export const findAndReplace =
         const replace = pairs[pairIndex][1]
         let start = 0
         // @ts-expect-error: TS is wrong, some of these children can be text.
-        let index = parent.children.indexOf(node)
+        const index = parent.children.indexOf(node)
         /** @type {Array<PhrasingContent>} */
         let nodes = []
         /** @type {number|undefined} */
@@ -188,7 +188,6 @@ export const findAndReplace =
 
         if (position === undefined) {
           nodes = [node]
-          index--
         } else {
           if (start < node.value.length) {
             nodes.push({type: 'text', value: node.value.slice(start)})
@@ -197,7 +196,7 @@ export const findAndReplace =
           parent.children.splice(index, 1, ...nodes)
         }
 
-        return index + nodes.length + 1
+        return index + nodes.length
       }
     }
   )