The text editor hopes to mark the wrong sentences in red, and the text editor uses markdown

Text editor I hope there are wrong sentences marked in red , Text editor used markdown
Rich text is a little difficult

    <div class="markDownBlock">
      <Markdown @on-ready="onReadyMarkdown" v-model="allQues"></Markdown>
<!--      @on-ready="onReadyMarkdown"-->
      <Markdown isPreview="true" class="topMarkDown"  v-model="errorContent"></Markdown>
<!--      <Markdown class="topMarkDown"  v-model="changedContent"></Markdown>-->
    </div>

markdown rely on

Two markdown One for previewing position: absolute; On the top of the editor On the right , Mask the original editor preview
The one shown should get Edited value , Then mark the wrong sentence red

.markDownBlock{
    
    position: relative;
  }
  .topMarkDown{
    
    position: absolute;
    top: 0;
    /*left: ;*/
    right: 0;
    width: 50%;
  }

When parsing Check if there is any repetition

  parse () {
    
        // let res= QuestionParser.getEachSub(this.allQues)
        let res = QuestionParser.parseQues(this.allQues)
        console.log(res)
    
        this.errorHappen = false

        this.parsedQuesList = res
        // this.parsedQuesList.
        this.errorContent = this.allQues
        for (let o of this.parsedQuesList) {
    
          // shortTitle
          let parsedDataTrimed = o.title.trim()


          for (let dbData of this.allQuesListDb) {
    
            if (dbData == null) {
    
              continue
            }
            let shortTitle = dbData.shortTitle
            if (shortTitle == null) {
    
              console.log(' No title ')
              console.log('dbData')
              console.log(dbData)
              continue
            }
            let shortTitleDbTrimed = dbData.shortTitle.trim()
            // let parsedDataTrimed= o.title.trim()
            if (shortTitleDbTrimed == parsedDataTrimed) {
    
              console.log(' It's the same  ')
              console.log(' In the database  ')
              console.log(shortTitleDbTrimed)
              console.log(' Now it is resolved ')
              console.log(parsedDataTrimed)
              this.errorHappen = true
              // this.allQues=this.allQues.replace(shortTitleDbTrimed,
              // '<span style=\'color: red;\' >' + shortTitleDbTrimed + '</span>')
              this.errorContent = this.errorContent.replace(shortTitleDbTrimed,
                '<span style=\'color: red;\' >' + shortTitleDbTrimed + '</span>')

            }
          }

        }
      },