diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index bd201c587..512d30d7c 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -36,8 +36,6 @@ jobs:
       - uses: actions/setup-python@v5
         with:
           python-version: '3.11'
-      - run: pip install poetry
-      - run: poetry install
       - name: Restore cached tessdata
         uses: actions/cache/restore@v4
         with:
@@ -45,6 +43,8 @@ jobs:
           enableCrossOsArchive: true
           fail-on-cache-miss: true
           key: v1-tessdata-${{ hashFiles('./install/common/download-tessdata.py') }}
+      - run: pip install poetry
+      - run: poetry install
       - name: Run CLI tests
         run: poetry run make test
       # Taken from: https://github.com/orgs/community/discussions/27149#discussioncomment-3254829
diff --git a/dangerzone/isolation_provider/base.py b/dangerzone/isolation_provider/base.py
index 71a4cc5ca..697a1bd18 100644
--- a/dangerzone/isolation_provider/base.py
+++ b/dangerzone/isolation_provider/base.py
@@ -172,8 +172,14 @@ def pixels_to_pdf_page(
             page_pdf_bytes = self.ocr_page(pixmap, ocr_lang)
         else:  # Don't OCR
             page_doc = fitz.Document()
-            page_doc.insert_file(pixmap)
-            page_pdf_bytes = page_doc.tobytes(deflate_images=True)
+            # Added in PyMuPDF 1.22.0 (commit 6a9c9d8175c307f7f3baf605c8632745f69a8b1b)
+            if hasattr(page_doc, "insert_file"):
+                page_doc.insert_file(pixmap)
+                page_pdf_bytes = page_doc.tobytes(deflate_images=True)
+            else:
+                page = page_doc.newPage()
+                page.insertImage(page.rect, pixmap=pixmap)
+                page_pdf_bytes = page_doc.write(deflate=True)
 
         return fitz.open("pdf", page_pdf_bytes)
 
@@ -240,12 +246,27 @@ def _convert(
         # Ensure nothing else is read after all bitmaps are obtained
         p.stdout.close()
 
-        safe_doc.save(document.output_filename)
+        if hasattr(safe_doc, "tobytes"):
+            pdf_bytes = safe_doc.tobytes()
+        else:
+            pdf_bytes = safe_doc.write()
+        with open(document.output_filename, "wb+") as f:
+            f.write(pdf_bytes)
 
         # TODO handle leftover code input
         text = "Converted document"
         self.print_progress(document, False, text, percentage)
 
+        if getattr(sys, "dangerzone_dev", False):
+            assert p.stderr
+            debug_log = read_debug_text(p.stderr, MAX_CONVERSION_LOG_CHARS)
+            log.info(
+                "Conversion output (doc to pixels)\n"
+                f"{DOC_TO_PIXELS_LOG_START}\n"
+                f"{debug_log}"  # no need for an extra newline here
+                f"{DOC_TO_PIXELS_LOG_END}"
+            )
+
     def print_progress(
         self, document: Document, error: bool, text: str, percentage: float
     ) -> None:
@@ -354,13 +375,3 @@ def doc_to_pixels_proc(
             self.ensure_stop_doc_to_pixels_proc(
                 document, p, timeout_grace=timeout_grace, timeout_force=timeout_force
             )
-
-            if getattr(sys, "dangerzone_dev", False):
-                assert p.stderr
-                debug_log = read_debug_text(p.stderr, MAX_CONVERSION_LOG_CHARS)
-                log.info(
-					"Conversion output (doc to pixels)\n"
-					f"{DOC_TO_PIXELS_LOG_START}\n"
-					f"{debug_log}"  # no need for an extra newline here
-					f"{DOC_TO_PIXELS_LOG_END}"
-                )
diff --git a/poetry.lock b/poetry.lock
index 381305090..1e8fec3b2 100644
--- a/poetry.lock
+++ b/poetry.lock
@@ -1001,13 +1001,13 @@ files = [
 
 [[package]]
 name = "urllib3"
-version = "2.2.1"
+version = "2.2.2"
 description = "HTTP library with thread-safe connection pooling, file post, and more."
 optional = false
 python-versions = ">=3.8"
 files = [
-    {file = "urllib3-2.2.1-py3-none-any.whl", hash = "sha256:450b20ec296a467077128bff42b73080516e71b56ff59a60a02bef2232c4fa9d"},
-    {file = "urllib3-2.2.1.tar.gz", hash = "sha256:d0570876c61ab9e520d776c38acbbb5b05a776d3f9ff98a5c8fd5162a444cf19"},
+    {file = "urllib3-2.2.2-py3-none-any.whl", hash = "sha256:a448b2f64d686155468037e1ace9f2d2199776e17f0a46610480d311f73e3472"},
+    {file = "urllib3-2.2.2.tar.gz", hash = "sha256:dd505485549a7a552833da5e6063639d0d177c04f23bc3864e41e5dc5f612168"},
 ]
 
 [package.extras]
@@ -1048,4 +1048,4 @@ test = ["big-O", "importlib-resources", "jaraco.functools", "jaraco.itertools",
 [metadata]
 lock-version = "2.0"
 python-versions = ">=3.9,<3.13"
-content-hash = "4b3f14e0c3a818fd7a45367131d27152e14f2ef2e7b3d95d9b5526cb43a2a204"
+content-hash = "bcc5b2685dec5e49a31e5704131d315ff5f60f485ba7d4c91c5a8bf3b927dca8"
diff --git a/pyproject.toml b/pyproject.toml
index 11d02bc20..be193b0a7 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -17,7 +17,7 @@ python = ">=3.9,<3.13"
 click = "*"
 appdirs = "*"
 PySide6 = "^6.7.1"
-PyMuPDF = "^1.23.8"
+PyMuPDF = "^1.16.11"
 colorama = "*"
 pyxdg = {version = "*", platform = "linux"}
 requests = "*"
diff --git a/stdeb.cfg b/stdeb.cfg
index 38148dcbb..79df78dd3 100644
--- a/stdeb.cfg
+++ b/stdeb.cfg
@@ -1,6 +1,6 @@
 [DEFAULT]
 Package3: dangerzone
-Depends3: podman, python3, python3-pyside2.qtcore, python3-pyside2.qtgui, python3-pyside2.qtwidgets, python3-pyside2.qtsvg, python3-appdirs, python3-click, python3-xdg, python3-colorama, python3-requests, python3-markdown, python3-packaging, python3-fitz (>= 1.19.0) | pyocr
+Depends3: podman, python3, python3-pyside2.qtcore, python3-pyside2.qtgui, python3-pyside2.qtwidgets, python3-pyside2.qtsvg, python3-appdirs, python3-click, python3-xdg, python3-colorama, python3-requests, python3-markdown, python3-packaging, python3-fitz (>= 1.19.0) | python3-pyocr
 Build-Depends: dh-python, python3, python3-setuptools, python3-stdeb
 Suite: bionic
 X-Python3-Version: >= 3.8