[Bug] EV3 cannot paste into the REPL

[BertLindeman]

Describe the bug
Running REPL in labs.pybricks.com on an EV3.
Want to copy a small program from the python window and paste into the REPL.
The copy succeeds (I can paste it in the python window).
But in the log window (is that how we call it?) where the REPL is active, the paste does nothing.
While it does work on the spike prime REPL.

To reproduce
Steps to reproduce the behavior:

1. Go to labs.python.com
2. Connect the EV3 via USB
3. Click on the REPL button
4. Select some text in the python window and 'copy'
5. Right click in the log window and select "Paste"
6. See nothing happening

Expected behavior
Would have expected the paste to work, like it does on a spike prime.
Both hubs have V4.0.0b8 as firmware:
('ev3', '4.0.0b8', 'ci-build-4793-v4.0.0b8-5-g0790d4f6 on 2026-03-24')
The version line here, also proves that copy in the REPL does work.

Screenshots
There is a saying that a picture is worth a 1000 words. Screenshots really help to identify and solve problems.

[dlech]

But in the log window (is that how we call it?

"Terminal pane"

5. Right click in the log window and select "Paste"

Did you deny clipboard permissions?

6. See nothing happening

Does CTRL+V work to paste?

[BertLindeman]

Did you deny clipboard permissions?

Not that I can find.
So many clipboard settings, cannot find a settings screen that looks like yours,
but would that depend on which pane it is allowed?
Paste in the source pane does work but only on the EV3, both on EV3 and primehub,
but paste in the terminal pane does not work on the EV3.
In the same "labs app" paste on the terminal pane running the primehub does work.

Does CTRL+V work to paste?

Tried CRTL-v CTRL-V and right-click 'select' Paste
None of them paste.

[EDIT]
Found the app-settings:

Went to linux Mint and have reset the settings there, so first paste asks for permission. Granted clipboard access.
Same "nothing pasted" both on labs and beta.pybricks.com..

Strange side note: going into REPL the REPL header is truncated at ~ 50 characters, until I un/replugged USB cable. Then the message was complete again.

[BertLindeman]

All tested on win11 [EDIT] on Google chrome app Version 147.0.7727.56 (Official Build) (64-bit).

• ❌ The city hub at V4.0.0b8 does not paste in the terminal pane.
• ❌✅ Technic hub at 3.6.1 does paste but not as neat as I would like, but some data gets pasted.
  ❌ Technic hub at V4.0.0b8 does not paste.
• primehub
  • ✅ connected via wifi does paste OK
  • ✅ connected via USB does paste OK

Will reboot windows again later and retry.

[EDIT] Reboot did not help. All the same.

[EDIT]Using MS-Edge no problem.

[BertLindeman]

The error I pasted in issue 2416 is in fact an error that pops up on the paste in the REPL window.

If I stop the REPL, the paste error 129 is shown and I thought it was caused by stopping the REPL, but it is the error already caused by the paste before the close.

Not so sure anymore about my statement

Using MS-Edge no problem.

It worked once, but now cannot confirm anymore.

[laurensvalk]

For me, pasting

print("Hello world")

works but

print("Hello world2")

does not, so pasting isn't necessarily broken, but reading (or echoing) beyond a certain number of characters might be broken.

I think it is reading broken specifically since we can use input to supress the echo and still reproduce the empty input.

[laurensvalk]

We've been working steadily on Pybricks Code the past weeks but should be getting back to the firmware side fairly soon.

[BertLindeman]

Thanks Laurens,

I would not have thought about the length of the to-be-pasted string.