Signature popup shrinks at the top

[ghost]

Description

The signature tooltip always opens above the completion point and can't go beyond the editor top border, so it progressively shrinks when the completion point is near the top, until disappearing altogether.

Reproduce

Expected behavior

It always opens at a reasonable height, downwards if upwards is not possible.

Context

• Operating System and version: Windows 11
• Browser and version: Chrome 135.0.7049.115
• JupyterLab version: 4.4.1
• Language server and version: python-lsp-server 1.12.2

Required: installed server extensions

❯ jupyter server extension list
Config dir: /home/carlos/.jupyter
Config dir: /home/carlos/.venvs/lab/etc/jupyter

jupyter_lsp enabled

- Validating jupyter_lsp...

jupyter_lsp 2.2.5 OK

jupyter_server_terminals enabled

- Validating jupyter_server_terminals...

jupyter_server_terminals 0.5.3 OK

jupyterlab enabled

- Validating jupyterlab...

Extension package jupyterlab took 0.1721s to import

jupyterlab 4.4.1 OK

jupyterlab_myst enabled

- Validating jupyterlab_myst...

jupyterlab_myst 2.4.2 OK

notebook_shim enabled

- Validating notebook_shim...

notebook_shim  OK
Config dir: /usr/local/etc/jupyter

Required: installed lab extensions

❯ jupyter labextension list
JupyterLab v4.4.1
/home/carlos/.venvs/lab/share/jupyter/labextensions
        jupyterlab-myst v2.4.2 enabled OK (python, jupyterlab_myst)
        jupyterlab_pygments v0.3.0 enabled OK (python, jupyterlab_pygments)
        @jupyter-lsp/jupyterlab-lsp v5.1.0 enabled OK (python, jupyterlab-lsp)
Disabled extensions:

@jupyterlab/completer-extension:base-service

@jupyterlab/fileeditor-extension:language-server

@jupyterlab/lsp-extension:settings

@jupyterlab/notebook-extension:language-server

Troubleshoot Output

$PATH:
	/home/carlos/.pyenv/shims
	/home/carlos/.pyenv/bin
	/home/carlos/.fury/fury_venv/bin
	/home/carlos/util
	/home/carlos/.local/bin
	/home/carlos/.venvs/base/bin
	/home/carlos/.venvs/lab/bin
	/home/carlos/.pyenv/bin
	/home/carlos/.fury/fury_venv/bin
	/home/carlos/util
	/home/carlos/.local/bin
	/home/carlos/.venvs/base/bin
	/usr/local/sbin
	/usr/local/bin
	/usr/sbin
	/usr/bin
	/sbin
	/bin
	/usr/games
	/usr/local/games
	/usr/lib/wsl/lib
	/mnt/c/WINDOWS/system32
	/mnt/c/WINDOWS
	/mnt/c/WINDOWS/System32/Wbem
	/mnt/c/WINDOWS/System32/WindowsPowerShell/v1.0/
	/mnt/c/WINDOWS/System32/OpenSSH/
	/mnt/c/Program Files/dotnet/
	/mnt/c/Program Files/Docker/Docker/resources/bin
	/mnt/c/Users/carlo/AppData/Local/Microsoft/WindowsApps
	/mnt/c/Users/carlo/AppData/Local/Programs/Microsoft VS Code/bin
	/snap/bin
sys.path:

/home/carlos/.venvs/lab/bin

/home/carlos/util

/home/carlos/.pyenv/versions/3.12.10/lib/python312.zip

/home/carlos/.pyenv/versions/3.12.10/lib/python3.12

/home/carlos/.pyenv/versions/3.12.10/lib/python3.12/lib-dynload

/home/carlos/.venvs/lab/lib/python3.12/site-packages
sys.executable:

/home/carlos/.venvs/lab/bin/python3.12
sys.version:

3.12.10 (main, Apr 26 2025, 17:02:28) [GCC 11.4.0]
platform.platform():

Linux-5.15.167.4-microsoft-standard-WSL2-x86_64-with-glibc2.35
which -a jupyter:

/home/carlos/.venvs/lab/bin/jupyter
pip list:

Package                   Version

------------------------- --------------

anyio                     4.9.0

argon2-cffi               23.1.0

argon2-cffi-bindings      21.2.0

arrow                     1.3.0

astroid                   3.3.9

asttokens                 3.0.0

async-lru                 2.0.5

attrs                     25.3.0

autopep8                  2.0.4

babel                     2.17.0

beautifulsoup4            4.13.4

bleach                    6.2.0

certifi                   2025.4.26

cffi                      1.17.1

charset-normalizer        3.4.1

comm                      0.2.2

debugpy                   1.8.14

decorator                 5.2.1

defusedxml                0.7.1

dill                      0.4.0

docstring-to-markdown     0.16

executing                 2.2.0

fastjsonschema            2.21.1

flake8                    7.1.2

fqdn                      1.5.1

h11                       0.16.0

httpcore                  1.0.9

httpx                     0.28.1

idna                      3.10

importlib_metadata        8.7.0

ipykernel                 6.29.5

ipython                   9.2.0

ipython_pygments_lexers   1.1.1

isoduration               20.11.0

isort                     6.0.1

jedi                      0.19.2

Jinja2                    3.1.6

json5                     0.12.0

jsonpointer               3.0.0

jsonschema                4.23.0

jsonschema-specifications 2025.4.1

jupyter_client            8.6.3

jupyter_core              5.7.2

jupyter-events            0.12.0

jupyter-lsp               2.2.5

jupyter_server            2.15.0

jupyter_server_terminals  0.5.3

jupyterlab                4.4.1

jupyterlab-lsp            5.1.0

jupyterlab_myst           2.4.2

jupyterlab_pygments       0.3.0

jupyterlab_server         2.27.3

MarkupSafe                3.0.2

matplotlib-inline         0.1.7

mccabe                    0.7.0

mistune                   3.1.3

nbclient                  0.10.2

nbconvert                 7.16.6

nbformat                  5.10.4

nest-asyncio              1.6.0

notebook_shim             0.2.4

overrides                 7.7.0

packaging                 25.0

pandocfilters             1.5.1

parso                     0.8.4

pexpect                   4.9.0

pip                       25.1

platformdirs              4.3.7

pluggy                    1.5.0

prometheus_client         0.21.1

prompt_toolkit            3.0.51

psutil                    7.0.0

ptyprocess                0.7.0

pure_eval                 0.2.3

pycodestyle               2.12.1

pycparser                 2.22

pydocstyle                6.3.0

pyflakes                  3.2.0

Pygments                  2.19.1

pylint                    3.3.6

python-dateutil           2.9.0.post0

python-json-logger        3.3.0

python-lsp-jsonrpc        1.1.2

python-lsp-server         1.12.2

pytoolconfig              1.3.1

PyYAML                    6.0.2

pyzmq                     26.4.0

referencing               0.36.2

requests                  2.32.3

rfc3339-validator         0.1.4

rfc3986-validator         0.1.1

rope                      1.13.0

rpds-py                   0.24.0

Send2Trash                1.8.3

setuptools                80.0.0

six                       1.17.0

sniffio                   1.3.1

snowballstemmer           2.2.0

soupsieve                 2.7

stack-data                0.6.3

terminado                 0.18.1

tinycss2                  1.4.0

tomlkit                   0.13.2

tornado                   6.4.2

traitlets                 5.14.3

types-python-dateutil     2.9.0.20241206

typing_extensions         4.13.2

ujson                     5.10.0

uri-template              1.3.0

urllib3                   2.4.0

wcwidth                   0.2.13

webcolors                 24.11.1

webencodings              0.5.1

websocket-client          1.8.0

whatthepatch              1.0.7

yapf                      0.43.0

zipp                      3.21.0