Spyder 5.5.5 Open File dialog does not show .py files

Issue Report Checklist

[ X] Searched the issues page for similar reports
[ X] Read the relevant sections of the Spyder Troubleshooting Guide and followed its advice
[ X] Reproduced the issue after updating with conda update spyder (or pip, if not using Anaconda)
[ ?] Could not reproduce inside jupyter qtconsole (if console-related) Sorry, I'm not familiar with jupyter qtconsole
[ X] Tried basic troubleshooting (if a bug/error)
- [X ] Restarted Spyder
- [ X] Reset preferences with spyder --reset
- [ X] Reinstalled the latest version of Anaconda
- [ X] Tried the other applicable steps from the Troubleshooting Guide
[ X] Completed the Problem Description, Steps to Reproduce and Version sections below

Problem Description

I just installed Spyder 5.5.5 in a fresh Conda environment (using conda install spyder). Whenever I try to open a file, the Open File dialog does not show .py files (it does show folders, and any other files in the current folder). Manually typing a .py filename in the File name box does work to open a file, but is a tad inconvenient.

What steps reproduce the problem?

Type Ctrl+O, click File --> Open, or click the "Open file" icon

What is the expected output? What do you see instead?

Expected: a dialog showing all files and folders in the current folder, including .py files Actual output: a dialog showing all files and folders in the current folder, except .py files

Paste Traceback/Error Below (if applicable)

Not applicable

Versions

Spyder version: 5.5.5 (conda)
Python version: 3.12.4 64-bit
Qt version: 5.15.8
PyQt5 version: 5.15.9
Operating System: Linux-6.5.0-44-generic-x86_64-with-glibc2.35

Dependencies

# Mandatory:
atomicwrites >=1.2.0             :  1.4.1 (OK)
chardet >=2.0.0                  :  5.2.0 (OK)
cloudpickle >=0.5.0              :  3.0.0 (OK)
cookiecutter >=1.6.0             :  2.6.0 (OK)
diff_match_patch >=20181111      :  20230430 (OK)
intervaltree >=3.0.2             :  3.1.0 (OK)
IPython >=8.13.0,<9.0.0,!=8.17.1 :  8.26.0 (OK)
jedi >=0.17.2,<0.20.0            :  0.19.1 (OK)
jellyfish >=0.7                  :  1.0.4 (OK)
jsonschema >=3.2.0               :  4.23.0 (OK)
keyring >=17.0.0                 :  25.2.1 (OK)
nbconvert >=4.0                  :  7.16.4 (OK)
numpydoc >=0.6.0                 :  1.7.0 (OK)
parso >=0.7.0,<0.9.0             :  0.8.4 (OK)
pexpect >=4.4.0                  :  4.9.0 (OK)
pickleshare >=0.4                :  0.7.5 (OK)
psutil >=5.3                     :  6.0.0 (OK)
pygments >=2.0                   :  2.18.0 (OK)
pylint >=3.1,<4                  :  3.2.5 (OK)
pylint_venv >=3.0.2              :  3.0.3 (OK)
pyls_spyder >=0.4.0              :  0.4.0 (OK)
pylsp >=1.11.0,<1.12.0           :  1.11.0 (OK)
pylsp_black >=2.0.0,<3.0.0       :  2.0.0 (OK)
qdarkstyle >=3.2.0,<3.3.0        :  3.2.3 (OK)
qstylizer >=0.2.2                :  0.2.3 (OK)
qtawesome >=1.3.1,<1.4.0         :  1.3.1 (OK)
qtconsole >=5.5.1,<5.6.0         :  5.5.2 (OK)
qtpy >=2.1.0                     :  2.4.1 (OK)
rtree >=0.9.7                    :  1.3.0 (OK)
setuptools >=49.6.0              :  71.0.1 (OK)
sphinx >=0.6.6                   :  7.4.5 (OK)
spyder_kernels >=2.5.2,<2.6.0    :  2.5.2 (OK)
textdistance >=4.2.0             :  4.6.2 (OK)
three_merge >=0.1.1              :  0.1.1 (OK)
watchdog >=0.10.3                :  4.0.1 (OK)
xdg >=0.26                       :  0.28 (OK)
zmq >=24.0.0                     :  26.0.3 (OK)

# Optional:
cython >=0.21                    :  None (NOK)
matplotlib >=3.0.0               :  3.9.1 (OK)
numpy >=1.7                      :  2.0.0 (OK)
pandas >=1.1.1                   :  2.2.2 (OK)
scipy >=0.17.0                   :  1.14.0 (OK)
sympy >=0.7.3                    :  None (NOK)

spyder-ide / spyder