How can I get the order of plots correct in an rmd? [How can I control the print-time of messages?]

As the minimal reproducible example below shows, plot 2 appears too late. How can I fix this?

It seems, the message screws everthing up. Most likely related: this and this.

---
title: "Run all test-cases"
author: "STCH"
date: "`r Sys.Date()`"
output:
  html_document:
    keep_md: yes
    number_sections: yes
    toc: yes
    toc_depth: 2
    code_folding: hide
  pdf_document:
    number_sections: yes
    toc: yes
    toc_depth: '2'
---

```{r setup, include=FALSE}
knitr::opts_chunk$set(echo = TRUE, fig.width = 10)
testfun <- function() {
    message("in testfun")
    Sys.sleep(10)
    plot(3, main = "testfun 3")
    return(0)
  }
```

# All test cases `decreasing.benefits = TRUE`

```{r}
for (i in 1){#c(1:7)) {
  cat("====================================================================\n")
  plot(1, main = "1")
  
  print("After plot 1, before plot 2")
  plot(2, main = "2")
  
  print("After plot 2, before plot 3 (Wrong!!??, appears BEFORE plot 2)")
  r <- testfun()
}
```

From the docs ?message:

message(..., domain = NULL, appendLF = TRUE)

so it seems you can only control the domain (which has to with translation) and the line ending.