diff --git a/.github/dependabot.yml b/.github/dependabot.yml
new file mode 100644
index 000000000..5ace4600a
--- /dev/null
+++ b/.github/dependabot.yml
@@ -0,0 +1,6 @@
+version: 2
+updates:
+  - package-ecosystem: "github-actions"
+    directory: "/"
+    schedule:
+      interval: "weekly"
diff --git a/.github/workflows/dev-cmd-check.yml b/.github/workflows/dev-cmd-check.yml
index b61ffa4bb..77e4a431e 100644
--- a/.github/workflows/dev-cmd-check.yml
+++ b/.github/workflows/dev-cmd-check.yml
@@ -27,7 +27,7 @@ jobs:
           - {os: ubuntu-latest, r: 'release', dev-package: "mlr-org/bbotk', 'mlr-org/mlr3learners', 'mlr-org/paradox"}
 
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
 
       - uses: r-lib/actions/setup-r@v2
         with:
diff --git a/.github/workflows/pkgdown.yml b/.github/workflows/pkgdown.yml
index 09f42a5a8..85cf2ff72 100644
--- a/.github/workflows/pkgdown.yml
+++ b/.github/workflows/pkgdown.yml
@@ -23,7 +23,7 @@ jobs:
     env:
       GITHUB_PAT: ${{ secrets.GITHUB_TOKEN }}
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
 
       - uses: r-lib/actions/setup-pandoc@v2
 
@@ -44,7 +44,7 @@ jobs:
 
       - name: Deploy
         if: github.event_name != 'pull_request'
-        uses: JamesIves/github-pages-deploy-action@v4.4.1
+        uses: JamesIves/github-pages-deploy-action@v4.5.0
         with:
           clean: false
           branch: gh-pages
diff --git a/.github/workflows/r-cmd-check.yml b/.github/workflows/r-cmd-check.yml
index fbd78ab3c..8d13d0e56 100644
--- a/.github/workflows/r-cmd-check.yml
+++ b/.github/workflows/r-cmd-check.yml
@@ -28,7 +28,7 @@ jobs:
           - {os: ubuntu-latest,   r: 'release'}
 
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
 
       - uses: r-lib/actions/setup-r@v2
         with:
diff --git a/DESCRIPTION b/DESCRIPTION
index 5e6b8a1ef..10fb81ecd 100644
--- a/DESCRIPTION
+++ b/DESCRIPTION
@@ -93,7 +93,7 @@ Config/testthat/edition: 3
 Config/testthat/parallel: true
 NeedsCompilation: no
 Roxygen: list(markdown = TRUE, r6 = FALSE)
-RoxygenNote: 7.2.3
+RoxygenNote: 7.2.3.9000
 VignetteBuilder: knitr
 Collate:
     'Graph.R'
diff --git a/NAMESPACE b/NAMESPACE
index a40fd7b44..c0b0975d9 100644
--- a/NAMESPACE
+++ b/NAMESPACE
@@ -148,6 +148,7 @@ import(mlr3)
 import(mlr3misc)
 import(paradox)
 importFrom(R6,R6Class)
+importFrom(data.table,as.data.table)
 importFrom(digest,digest)
 importFrom(stats,setNames)
 importFrom(utils,bibentry)
diff --git a/NEWS.md b/NEWS.md
index a4ecaa7a6..867ed08a4 100644
--- a/NEWS.md
+++ b/NEWS.md
@@ -1,7 +1,9 @@
 # mlr3pipelines 0.5.0-9000
 
-* `pipeline_bagging()` gets the `replace` argument.
-* Compatibility with upcoming paradox release
+* `pipeline_bagging()` gets the `replace` argument (old behaviour `FALSE` by default).
+* Feature: The `$add_pipeop()` method got an argument `clone` (old behaviour `TRUE` by default).
+* Bugfix: `PipeOpFeatureUnion` in some rare cases dropped variables called `"x"`.
+* Compatibility with upcoming paradox release.
 
 # mlr3pipelines 0.5.0-2
 
diff --git a/R/Graph.R b/R/Graph.R
index 8cc95a0ae..7df319808 100644
--- a/R/Graph.R
+++ b/R/Graph.R
@@ -59,7 +59,7 @@
 #' * `phash` :: `character(1)` \cr
 #'   Stores a checksum calculated on the [`Graph`] configuration, which includes all [`PipeOp`] hashes
 #'   *except* their `$param_set$values`, and a hash of `$edges`.
-#' * `keep_results` :: `logical(1)` \cr
+#' * `keep_results` :: `logical(1)`\cr
 #'   Whether to store intermediate results in the [`PipeOp`]'s `$.result` slot, mostly for debugging purposes. Default `FALSE`.
 #' * `man` :: `character(1)`\cr
 #'   Identifying string of the help page that shows with `help()`.
@@ -69,13 +69,14 @@
 #'   (`logical(1)`) -> `character` \cr
 #'   Get IDs of all [`PipeOp`]s. This is in order that [`PipeOp`]s were added if
 #'   `sorted` is `FALSE`, and topologically sorted if `sorted` is `TRUE`.
-#' * `add_pipeop(op)` \cr
-#'   ([`PipeOp`] | [`Learner`][mlr3::Learner] | [`Filter`][mlr3filters::Filter] | `...`) -> `self` \cr
+#' * `add_pipeop(op, clone = TRUE)` \cr
+#'   ([`PipeOp`] | [`Learner`][mlr3::Learner] | [`Filter`][mlr3filters::Filter] | `...`, `logical(1)`) -> `self` \cr
 #'   Mutates [`Graph`] by adding a [`PipeOp`] to the [`Graph`]. This does not add any edges, so the new [`PipeOp`]
 #'   will not be connected within the [`Graph`] at first.\cr
 #'   Instead of supplying a [`PipeOp`] directly, an object that can naturally be converted to a [`PipeOp`] can also
 #'   be supplied, e.g. a [`Learner`][mlr3::Learner] or a [`Filter`][mlr3filters::Filter]; see [`as_pipeop()`].
-#'   The argument given as `op` is always cloned; to access a `Graph`'s [`PipeOp`]s by-reference, use `$pipeops`.\cr
+#'   The argument given as `op` is cloned if `clone` is `TRUE` (default); to access a `Graph`'s [`PipeOp`]s
+#'   by-reference, use `$pipeops`.\cr
 #'   Note that `$add_pipeop()` is a relatively low-level operation, it is recommended to build graphs using [`%>>%`].
 #' * `add_edge(src_id, dst_id, src_channel = NULL, dst_channel = NULL)` \cr
 #'   (`character(1)`, `character(1)`,
@@ -181,8 +182,8 @@ Graph = R6Class("Graph",
       topo_sort(tmp)$id
     },
 
-    add_pipeop = function(op) {
-      op = as_pipeop(op, clone = TRUE)
+    add_pipeop = function(op, clone = TRUE) {
+      op = as_pipeop(op, clone = assert_flag(clone))
       if (op$id %in% names(self$pipeops)) {
         stopf("PipeOp with id '%s' already in Graph", op$id)
       }
diff --git a/R/PipeOpFeatureUnion.R b/R/PipeOpFeatureUnion.R
index 8a2c1b4ce..bbc1e890b 100644
--- a/R/PipeOpFeatureUnion.R
+++ b/R/PipeOpFeatureUnion.R
@@ -202,6 +202,7 @@ cbind_tasks = function(inputs, assert_targets_equal, inprefix) {
   # again done by reference
   new_features = unlist(c(list(data.table(x = vector(length = task$nrow))),
     map(tail(inputs, -1L), .f = function(y) y$data(ids, cols = y$feature_names))), recursive = FALSE)
+  names(new_features)[1] = make.unique(rev(names(new_features)))[[length(new_features)]]
 
   # we explicitly have to subset to the unique column names, otherwise task$cbind() complains for data.table backends
   new_features = new_features[unique(names(new_features))]
diff --git a/R/assert_graph.R b/R/assert_graph.R
index 03c723e14..fadaa22b7 100644
--- a/R/assert_graph.R
+++ b/R/assert_graph.R
@@ -39,8 +39,10 @@ as_graph = function(x, clone = FALSE) {
 }
 
 #' @export
-as_graph.default = function(x, clone = FALSE) {
-  Graph$new()$add_pipeop(x)  # add_pipeop always clones and checks automatically for convertability
+as_graph.default = function(x, clone = TRUE) {
+  # different default than other methods for backwards compatibility
+  # previously $add_pipeop() always cloned its input
+  Graph$new()$add_pipeop(x, clone = clone)
 }
 
 #' @export
diff --git a/man/Graph.Rd b/man/Graph.Rd
index 8da82dac3..ab76b20c8 100644
--- a/man/Graph.Rd
+++ b/man/Graph.Rd
@@ -69,7 +69,7 @@ Stores a checksum calculated on the \code{\link{Graph}} configuration, which inc
 \item \code{phash} :: \code{character(1)} \cr
 Stores a checksum calculated on the \code{\link{Graph}} configuration, which includes all \code{\link{PipeOp}} hashes
 \emph{except} their \verb{$param_set$values}, and a hash of \verb{$edges}.
-\item \code{keep_results} :: \code{logical(1)} \cr
+\item \code{keep_results} :: \code{logical(1)}\cr
 Whether to store intermediate results in the \code{\link{PipeOp}}'s \verb{$.result} slot, mostly for debugging purposes. Default \code{FALSE}.
 \item \code{man} :: \code{character(1)}\cr
 Identifying string of the help page that shows with \code{help()}.
@@ -83,13 +83,14 @@ Identifying string of the help page that shows with \code{help()}.
 (\code{logical(1)}) -> \code{character} \cr
 Get IDs of all \code{\link{PipeOp}}s. This is in order that \code{\link{PipeOp}}s were added if
 \code{sorted} is \code{FALSE}, and topologically sorted if \code{sorted} is \code{TRUE}.
-\item \code{add_pipeop(op)} \cr
-(\code{\link{PipeOp}} | \code{\link[mlr3:Learner]{Learner}} | \code{\link[mlr3filters:Filter]{Filter}} | \code{...}) -> \code{self} \cr
+\item \code{add_pipeop(op, clone = TRUE)} \cr
+(\code{\link{PipeOp}} | \code{\link[mlr3:Learner]{Learner}} | \code{\link[mlr3filters:Filter]{Filter}} | \code{...}, \code{logical(1)}) -> \code{self} \cr
 Mutates \code{\link{Graph}} by adding a \code{\link{PipeOp}} to the \code{\link{Graph}}. This does not add any edges, so the new \code{\link{PipeOp}}
 will not be connected within the \code{\link{Graph}} at first.\cr
 Instead of supplying a \code{\link{PipeOp}} directly, an object that can naturally be converted to a \code{\link{PipeOp}} can also
 be supplied, e.g. a \code{\link[mlr3:Learner]{Learner}} or a \code{\link[mlr3filters:Filter]{Filter}}; see \code{\link[=as_pipeop]{as_pipeop()}}.
-The argument given as \code{op} is always cloned; to access a \code{Graph}'s \code{\link{PipeOp}}s by-reference, use \verb{$pipeops}.\cr
+The argument given as \code{op} is cloned if \code{clone} is \code{TRUE} (default); to access a \code{Graph}'s \code{\link{PipeOp}}s
+by-reference, use \verb{$pipeops}.\cr
 Note that \verb{$add_pipeop()} is a relatively low-level operation, it is recommended to build graphs using \code{\link{\%>>\%}}.
 \item \code{add_edge(src_id, dst_id, src_channel = NULL, dst_channel = NULL)} \cr
 (\code{character(1)}, \code{character(1)},
diff --git a/pkgdown/_pkgdown.yml b/pkgdown/_pkgdown.yml
index 9e556cf79..1f3a711ca 100644
--- a/pkgdown/_pkgdown.yml
+++ b/pkgdown/_pkgdown.yml
@@ -35,6 +35,9 @@ navbar:
     rss:
       icon: fa-rss
       href: https://mlr-org.com/
+    extending:
+      text: Extending
+      href: extending.html
 
 reference:
   - title: Package
diff --git a/tests/testthat/test_pipeop_featureunion.R b/tests/testthat/test_pipeop_featureunion.R
index 9687d1afb..f408fb196 100644
--- a/tests/testthat/test_pipeop_featureunion.R
+++ b/tests/testthat/test_pipeop_featureunion.R
@@ -257,3 +257,18 @@ test_that("featureunion - cbind_tasks - duplicates", {
   expect_equal(output$data(cols = "x"), inputs[[1L]]$data(cols = "x"))
   expect_equivalent(output$data(cols = c("Species", new_iris_names)), task1$data())
 })
+
+test_that("featureunion - does not drop 'x' column", {
+  task1 = as_task_regr(data.table(
+    z = 1:10,
+    y = 1:10
+  ), target = "y")
+
+  task2 = as_task_regr(data.table(
+    x = 1:10,
+    y = 1:10
+  ), target = "y")
+
+  taskout = po("featureunion")$train(list(task1, task2))[[1L]]
+  expect_permutation(taskout$feature_names, c("x", "z"))
+})