[Bug]: The service get stuck if I tap 'confirmed' twice(or more) consecutively

[WannaTen]

Is there an existing issue for the same bug?

• I have checked the troubleshooting document at https://docs.all-hands.dev/modules/usage/troubleshooting
• I have checked the existing issues.

Describe the bug

I activated confirmation mode while in browser mode. When the confirmation button shows up on the left, double-clicking(or even more clicks) it causes the agent to halt every time. To resume, I have to click the 'pause' button in the lower-left corner, then click 'continue'.

Current OpenHands version

0.9.3

Installation and Configuration

not used any command or specific configuration.

Model and Agent

No response

Operating System

WSL

Reproduction Steps

1. open webUI
2. open Confirm Mode with CodeActagent
3. click the confirm button twice or more
4. stuck....

Logs, Errors, Screenshots, and Additional Context

click it twice or more:

then the logger output like this, output two NullObservation, which made the whole process stuck:

The logger output is from the code I added for debug:

only after I clicked pause then continue, the whole process continue:

[WannaTen]

23:36:38 - openhands:INFO: session.py:139 - Server event
23:36:38 - OBSERVATION
AgentStateChangedObservation(content='', agent_state=<AgentState.RUNNING: 'running'>, observation='agent_state_changed')
23:36:38 - openhands:INFO: session.py:139 - Server event
23:36:38 - OBSERVATION
AgentStateChangedObservation(content='', agent_state='user_confirmed', observation='agent_state_changed')
23:36:38 - openhands:INFO: session.py:139 - Server event
23:36:38 - OBSERVATION
NullObservation(content='', observation='null')
23:36:38 - OBSERVATION
NullObservation(content='', observation='null')
23:36:38 - openhands:INFO: runtime.py:307 -
-----------------------------------Container logs:-----------------------------------
    |INFO:     172.17.0.1:40520 - "GET /alive HTTP/1.1" 200 OK
    |INFO:     172.17.0.1:40524 - "POST /execute_action HTTP/1.1" 200 OK
--------------------------------------------------------------------------------
23:36:38 - openhands:INFO: runtime.py:414 - Awaiting session
23:36:38 - openhands:INFO: runtime.py:307 -
-----------------------------------Container logs:-----------------------------------
    |INFO:     172.17.0.1:58818 - "GET /alive HTTP/1.1" 200 OK
    |INFO:     172.17.0.1:58822 - "POST /list_files HTTP/1.1" 200 OK
--------------------------------------------------------------------------------
INFO:     127.0.0.1:58926 - "GET /api/list-files HTTP/1.1" 200 OK
23:36:38 - openhands:INFO: runtime.py:307 -
-----------------------------------Container logs:-----------------------------------
    |INFO:     172.17.0.1:58836 - "GET /alive HTTP/1.1" 200 OK
    |INFO:     172.17.0.1:58848 - "POST /execute_action HTTP/1.1" 200 OK
--------------------------------------------------------------------------------
23:36:38 - openhands:INFO: runtime.py:414 - Awaiting session
23:36:38 - openhands:INFO: runtime.py:307 -
-----------------------------------Container logs:-----------------------------------
    |INFO:     172.17.0.1:58858 - "GET /alive HTTP/1.1" 200 OK
    |INFO:     172.17.0.1:58870 - "POST /list_files HTTP/1.1" 200 OK
--------------------------------------------------------------------------------
INFO:     127.0.0.1:58939 - "GET /api/list-files HTTP/1.1" 200 OK
23:36:38 - openhands:INFO: runtime.py:307 -
-----------------------------------Container logs:-----------------------------------
    |INFO:     172.17.0.1:58874 - "GET /alive HTTP/1.1" 200 OK
    |INFO:     172.17.0.1:58880 - "POST /execute_action HTTP/1.1" 200 OK
--------------------------------------------------------------------------------
23:36:39 - openhands:INFO: runtime.py:414 - Awaiting session
23:36:39 - openhands:INFO: runtime.py:307 -
-----------------------------------Container logs:-----------------------------------
    |INFO:     172.17.0.1:58892 - "GET /alive HTTP/1.1" 200 OK
    |INFO:     172.17.0.1:58906 - "POST /list_files HTTP/1.1" 200 OK
--------------------------------------------------------------------------------
INFO:     127.0.0.1:58926 - "GET /api/list-files HTTP/1.1" 200 OK
23:41:41 - OBSERVATION
AgentStateChangedObservation(content='', agent_state='paused', observation='agent_state_changed')
23:41:41 - openhands:INFO: session.py:139 - Server event
23:41:41 - OBSERVATION
NullObservation(content='', observation='null')
23:41:41 - openhands:INFO: runtime.py:307 -
-----------------------------------Container logs:-----------------------------------
    |INFO:     172.17.0.1:58918 - "GET /alive HTTP/1.1" 200 OK
    |INFO:     172.17.0.1:58928 - "POST /execute_action HTTP/1.1" 200 OK
--------------------------------------------------------------------------------
23:41:41 - openhands:INFO: runtime.py:414 - Awaiting session
INFO:     127.0.0.1:59511 - "GET /api/list-files HTTP/1.1" 200 OK
23:41:50 - OBSERVATION
AgentStateChangedObservation(content='', agent_state='running', observation='agent_state_changed')
23:41:50 - openhands:INFO: session.py:139 - Server event
23:41:50 - OBSERVATION
NullObservation(content='', observation='null')
23:41:50 - openhands:INFO: runtime.py:307 -

-----------------------------------Container logs:-----------------------------------
    |INFO:     172.17.0.1:38586 - "GET /alive HTTP/1.1" 200 OK
    |INFO:     172.17.0.1:38602 - "POST /list_files HTTP/1.1" 200 OK
    |INFO:     172.17.0.1:38604 - "GET /alive HTTP/1.1" 200 OK
    |INFO:     172.17.0.1:38620 - "POST /execute_action HTTP/1.1" 200 OK
--------------------------------------------------------------------------------
23:41:50 - openhands:INFO: runtime.py:414 - Awaiting session
23:41:50 - openhands:INFO: runtime.py:307 -
-----------------------------------Container logs:-----------------------------------
    |INFO:     172.17.0.1:50862 - "GET /alive HTTP/1.1" 200 OK
    |INFO:     172.17.0.1:50878 - "POST /list_files HTTP/1.1" 200 OK
--------------------------------------------------------------------------------