diff --git a/pipcl.py b/pipcl.py
index bca1ad1b3..9f3c93538 100644
--- a/pipcl.py
+++ b/pipcl.py
@@ -914,10 +914,19 @@ def tag_abi(self):
         '''
         ABI tag.
         '''
+        Py_GIL_DISABLED = sysconfig.get_config_var('Py_GIL_DISABLED')
         if self.tag_abi_:
             return self.tag_abi_
         elif self.py_limited_api:
+            assert Py_GIL_DISABLED != 1, \
+                    f'py_limited_api and Py_GIL_DISABLED are not supported together as of 2026-02-20, e.g. see PEP 803 and PEP 809.'
             return 'abi3'
+        elif Py_GIL_DISABLED == 1:
+            ret = ''
+            ret += 'cp'
+            ret += ''.join(platform.python_version().split('.')[:2])
+            ret += 't'
+            return ret
         else:
             return 'none'
 
diff --git a/src/extra.i b/src/extra.i
index 8f4e79c63..cd3fce901 100644
--- a/src/extra.i
+++ b/src/extra.i
@@ -3424,6 +3424,7 @@ int _as_blocks(fz_stext_block *block, fz_rect tp_rect, PyObject *lines, int bloc
     PyObject *text = NULL;
     fz_rect blockrect;
     mupdf::FzBuffer res;
+    int last_char;
     while (block)
     {
         switch (block->type)
@@ -3438,7 +3439,7 @@ int _as_blocks(fz_stext_block *block, fz_rect tp_rect, PyObject *lines, int bloc
             case FZ_STEXT_BLOCK_TEXT:
                 blockrect = fz_empty_rect;
                 res = mupdf::fz_new_buffer(1024);
-                int last_char;
+                last_char = 10;
                 for (fz_stext_line* line = block->u.t.first_line; line; line = line->next)
                 {
                     fz_rect linerect = fz_empty_rect;
diff --git a/tests/resources/test_4755.pdf b/tests/resources/test_4755.pdf
new file mode 100644
index 000000000..61b4d3862
Binary files /dev/null and b/tests/resources/test_4755.pdf differ
diff --git a/tests/test_4767.py b/tests/test_4767.py
index 433df6ddc..e8a88fe51 100644
--- a/tests/test_4767.py
+++ b/tests/test_4767.py
@@ -4,6 +4,7 @@
 import pymupdf
 import subprocess
 import sys
+import sysconfig
 
 
 def test_4767():
@@ -66,36 +67,51 @@ def get_paths():
                 paths.append(path)
         return paths
     
+    def get_stdout(cp):
+        '''
+        Strips free-threading warning.
+        '''
+        stdout = cp.stdout
+        if sysconfig.get_config_var('Py_GIL_DISABLED') == 1:
+            line0, stdout = stdout.split('\n', 1)
+            assert 'The global interpreter lock (GIL) has been enabled to load module \'pymupdf._extra\',' in line0
+        return stdout
+    
     cp = run(f'cd {testdir}/one/two && {sys.executable} -m pymupdf embed-extract {path} -name evil_entry')
-    print(cp.stdout)
     assert cp.returncode
-    assert cp.stdout == 'refusing to write stored name outside current directory: ../../test.txt\n'
+    stdout = get_stdout(cp)
+    print(f'{stdout=}')
+    assert stdout == 'refusing to write stored name outside current directory: ../../test.txt\n'
     assert not get_paths()
     
     cp = run(f'cd {testdir}/one/two && {sys.executable} -m pymupdf embed-extract {path} -name evil_entry -unsafe')
     assert cp.returncode == 0
-    assert cp.stdout == "saved entry 'evil_entry' as '../../test.txt'\n"
+    stdout = get_stdout(cp)
+    assert stdout == "saved entry 'evil_entry' as '../../test.txt'\n"
     paths = get_paths()
     print(f'{paths=}')
     assert paths == [f'{testdir}/test.txt']
     
     cp = run(f'cd {testdir}/one/two && {sys.executable} -m pymupdf embed-extract {path} -name evil_entry2')
     assert not cp.returncode
-    assert cp.stdout == "saved entry 'evil_entry2' as 'test2.txt'\n"
+    stdout = get_stdout(cp)
+    assert stdout == "saved entry 'evil_entry2' as 'test2.txt'\n"
     paths = get_paths()
     print(f'{paths=}')
     assert paths == [f'{testdir}/test.txt', f'{testdir}/one/two/test2.txt']
     
     cp = run(f'cd {testdir}/one/two && {sys.executable} -m pymupdf embed-extract {path} -name evil_entry2')
     assert cp.returncode
-    assert cp.stdout == "refusing to overwrite existing file with stored name: test2.txt\n"
+    stdout = get_stdout(cp)
+    assert stdout == "refusing to overwrite existing file with stored name: test2.txt\n"
     paths = get_paths()
     print(f'{paths=}')
     assert paths == [f'{testdir}/test.txt', f'{testdir}/one/two/test2.txt']
     
     cp = run(f'cd {testdir}/one/two && {sys.executable} -m pymupdf embed-extract {path} -name evil_entry2 -unsafe')
     assert not cp.returncode
-    assert cp.stdout == "saved entry 'evil_entry2' as 'test2.txt'\n"
+    stdout = get_stdout(cp)
+    assert stdout == "saved entry 'evil_entry2' as 'test2.txt'\n"
     paths = get_paths()
     print(f'{paths=}')
     assert paths == [f'{testdir}/test.txt', f'{testdir}/one/two/test2.txt']
diff --git a/tests/test_annots.py b/tests/test_annots.py
index b6df366f2..122968291 100644
--- a/tests/test_annots.py
+++ b/tests/test_annots.py
@@ -3,6 +3,7 @@
 Test PDF annotation insertions.
 """
 
+import copy
 import os
 import platform
 
@@ -674,3 +675,46 @@ def test_4447():
     
     path_out = os.path.normpath(f'{__file__}/../../tests/test_4447.pdf')
     document.save(path_out)
+
+
+def test_4755():
+    print()
+    path = os.path.normpath(f'{__file__}/../../tests/resources/test_4755.pdf')
+    path_out = os.path.normpath(f'{__file__}/../../tests/test_4755_out.pdf')
+    
+    with pymupdf.open(path) as document:
+        for page_i, page in enumerate(document):
+            print(f'{page_i=}')
+            caret = page.add_caret_annot((50,50))
+
+            colours = [
+                    (0, 0, 1),
+                    (0, 1, 0),
+                    (1, 0, 0),
+                    ]
+            for annot_i, annot in enumerate(page.annots()):
+                print(f'{annot_i=}')
+                #if annot_i != 2:
+                #    continue
+                before_rect = copy.deepcopy(annot.rect)
+
+                def draw_rectangle(rect, c, w):
+                    drect = page.add_freetext_annot(rect, str(annot_i), text_color=c)
+                    drect.set_border(width=w)
+                    drect.update()
+
+                colour = colours[annot_i]
+                print(f'{colour=}')
+                draw_rectangle(annot.rect, colour, .3)
+
+                print(f'before: {annot.rect}=')
+                annot.set_rect(annot.rect)
+                print(f' after: {annot.rect}=')
+
+                print(f'difference: {annot.rect-before_rect=}')
+
+                draw_rectangle(annot.rect, (0, 1, 0), .3)
+                print()
+        document.save(path_out)
+        print(f'    {path=}.')
+        print(f'{path_out=}.')
diff --git a/tests/test_general.py b/tests/test_general.py
index 7449010c0..96d070f1b 100644
--- a/tests/test_general.py
+++ b/tests/test_general.py
@@ -2004,7 +2004,7 @@ def test_4392():
         print('test_4392(): not running on Pyodide - cannot run child processes.')
         return
         
-    print()
+    print('', flush=1)
     path = os.path.normpath(f'{__file__}/../../tests/test_4392.py')
     with open(path, 'w') as f:
         f.write('import pymupdf\n')
@@ -2024,15 +2024,22 @@ def test_4392():
     e3 = subprocess.run(command, shell=1, check=0).returncode
     print(f'{e3=}')
     
-    print(f'{e1=} {e2=} {e3=}')
+    print(f'{e1=} {e2=} {e3=}', flush=1)
     
-    print(f'{pymupdf.swig_version=}')
-    print(f'{pymupdf.swig_version_tuple=}')
+    print(f'{pymupdf.swig_version=}', flush=1)
+    print(f'{pymupdf.swig_version_tuple=}', flush=1)
     
     assert e1 == 5
     if pymupdf.swig_version_tuple >= (4, 4):
-        assert e2 == 5
-        assert e3 == 0
+        if sysconfig.get_config_var('Py_GIL_DISABLED') == 1:
+            assert e2 == 4
+        else:
+            assert e2 == 5
+        if sysconfig.get_config_var('Py_GIL_DISABLED') == 1:
+            # GIL warning results in failure because of -Werror.
+            assert e3 == 1
+        else:
+            assert e3 == 0
     else:
         # We get SEGV's etc with older swig.
         if platform.system() == 'Windows':
diff --git a/tests/test_pixmap.py b/tests/test_pixmap.py
index 54128e523..bfbf3c565 100644
--- a/tests/test_pixmap.py
+++ b/tests/test_pixmap.py
@@ -11,6 +11,7 @@
 import os
 import platform
 import re
+import shutil
 import subprocess
 import sys
 import tempfile
@@ -284,6 +285,10 @@ def test_3493():
     import subprocess
     
     root = os.path.abspath(f'{__file__}/../..')
+    
+    venv = f'{root}/tests/resources/test_3493_venv'
+    shutil.rmtree(venv, ignore_errors=1)
+    
     in_path = f'{root}/tests/resources/test_3493.epub'
     
     def run(command, check=1, stdout=None):
@@ -319,7 +324,7 @@ def run_code(code, code_path, *, check=True, venv=None, venv_args='', pythonpath
             ,
             f'{root}/tests/resources/test_3493_gi.py',
             check=0,
-            venv=f'{root}/tests/resources/test_3493_venv',
+            venv=venv,
             venv_args='--system-site-packages',
             stdout=subprocess.PIPE,
             )