diff --git a/.github/workflows/R-CMD-check.yaml b/.github/workflows/R-CMD-check.yaml
index 87e20eb..6cf54b6 100644
--- a/.github/workflows/R-CMD-check.yaml
+++ b/.github/workflows/R-CMD-check.yaml
@@ -35,7 +35,7 @@ jobs:
       fail-fast: false
       matrix:
         config:
-          #- {os: windows-latest, r: 'release'}
+          - {os: windows-latest, r: 'release'}
           - {os: ubuntu-latest, r: "release", rspm: "https://packagemanager.rstudio.com/cran/__linux__/focal/latest"}
 
     env:
@@ -93,7 +93,7 @@ jobs:
       - name: Install dependencies (force ggplot2 v3.5.2 first)
         run: |
           install.packages('remotes')
-          # Instal ggplot2 3.5.2 first
+          # Install ggplot2 3.5.2 first (was done due to temporary incompatibility of CroPlotR with ggplot 4.0.0, to remove when CroPlotR 1.0.0 will be released)
           remotes::install_version("ggplot2", version = "3.5.2", upgrade = "never")
 
           # Instal dependencies without upgrade
@@ -106,10 +106,13 @@ jobs:
           remotes::install_github("SticsRPacks/SticsRFiles@main", dependencies = FALSE, upgrade = "never")
         shell: Rscript {0}
 
-      #- name: Install testthat 3.1.8
-      #  run: Rscript -e "install.packages('https://cran.r-project.org/src/contrib/Archive/testthat/testthat_3.1.8.tar.gz', repos = NULL, type = 'source')"
-      - name: Install testthat
-        run: Rscript -e "install.packages('testthat')"
+      - name: Install testthat 3.1.8 # there is a problem with testthat >= 3.1.8, tests crash at the end for an unknown reason although they all pass
+        run: |
+          Rscript -e 'install.packages("ellipsis")'
+          Rscript -e 'remotes::install_version("testthat", version = "3.1.8")'
+      # Rscript -e "install.packages('https://cran.r-project.org/src/contrib/Archive/testthat/testthat_3.1.8.tar.gz', repos = NULL, type = 'source')"
+      #- name: Install testthat
+      #  run: Rscript -e "install.packages('testthat')"
         
       - name: Check
         env: