diff --git a/osc/commands_git/pr_get.py b/osc/commands_git/pr_get.py
index 605db13c..c4505974 100644
--- a/osc/commands_git/pr_get.py
+++ b/osc/commands_git/pr_get.py
@@ -53,6 +53,9 @@ class PullRequestGetCommand(osc.commandline_git.GitObsCommand):
                 print(tty.colorize("Timeline:", "bold"))
                 timeline = gitea_api.IssueTimelineEntry.list(self.gitea_conn, owner, repo, pull)
                 for entry in timeline:
+                    if entry._data is None:
+                        print(f"{tty.colorize('ERROR', 'red,bold,blink')}: Gitea returned ``None`` instead of a timeline entry")
+                        continue
                     text, body = entry.format()
                     if text is None:
                         continue
diff --git a/osc/commands_git/pr_review_interactive.py b/osc/commands_git/pr_review_interactive.py
index 9d359b8c..926e45b5 100644
--- a/osc/commands_git/pr_review_interactive.py
+++ b/osc/commands_git/pr_review_interactive.py
@@ -228,6 +228,9 @@ class PullRequestReviewInteractiveCommand(osc.commandline_git.GitObsCommand):
         timeline_lines = []
         timeline_lines.append(tty.colorize("Timeline:", "bold"))
         for entry in timeline:
+            if entry._data is None:
+                timeline_lines.append(f"{tty.colorize('ERROR', 'red,bold,blink')}: Gitea returned ``None`` instead of a timeline entry")
+                continue
             text, body = entry.format()
             if text is None:
                 continue
diff --git a/osc/gitea_api/common.py b/osc/gitea_api/common.py
index a6a9779b..26b6ff4b 100644
--- a/osc/gitea_api/common.py
+++ b/osc/gitea_api/common.py
@@ -12,7 +12,18 @@ from .connection import GiteaHTTPResponse
 
 
 class GiteaModel:
-    def __init__(self, data, *, response: Optional[GiteaHTTPResponse] = None, conn: Optional[Connection] = None):
+    def __init__(
+        self,
+        data,
+        *,
+        check_data: bool = True,
+        response: Optional[GiteaHTTPResponse] = None,
+        conn: Optional[Connection] = None,
+    ):
+        if check_data and not isinstance(data, dict):
+            # Gitea sometimes fails to serialize an object and returns ``None`` instead
+            raise ValueError(f"Unable to instantiate model {self.__class__.__name__} from the following data: {data}")
+
         self._data = data
         self._response = response
         self._conn = conn
diff --git a/osc/gitea_api/issue_timeline_entry.py b/osc/gitea_api/issue_timeline_entry.py
index b39d4067..02b8a90f 100644
--- a/osc/gitea_api/issue_timeline_entry.py
+++ b/osc/gitea_api/issue_timeline_entry.py
@@ -235,6 +235,7 @@ class IssueTimelineEntry(GiteaModel):
     ) -> List["IssueTimelineEntry"]:
         """
         List issue timeline entries (applicable to issues and pull request).
+        HACK: the resulting list may contain instances wrapping ``None`` instead of dictionary with data!
 
         :param conn: Gitea ``Connection`` instance.
         :param owner: Owner of the repo.
@@ -246,5 +247,5 @@ class IssueTimelineEntry(GiteaModel):
         }
         url = conn.makeurl("repos", owner, repo, "issues", str(number), "timeline", query=q)
         response = conn.request("GET", url)
-        obj_list = [cls(i, response=response, conn=conn) for i in response.json() or []]
+        obj_list = [cls(i, response=response, conn=conn, check_data=False) for i in response.json() or []]
         return obj_list