1744774 - Screenshot tool adds border to image

Status: NEW

(Firefox :: Screenshots, defect, P3)

Description

[luke.leheny]

Attachment: signal-2021-12-07-102732_001.jpeg

User Agent: Mozilla/5.0 (X11; Linux x86_64; rv:94.0) Gecko/20100101 Firefox/94.0

Steps to reproduce:

(Firefox 94 on Arch Linux 64-bit)

1. Press Ctrl+Shift+S to activate screenshot tool
2. Select an image that has contrast with the background of the page
3. Paste image somewhere it can be viewed/inspected
4. Image has border on left side, and sometimes top side

Actual results:

Either the image has extra width & height, or the screenshot itself is offset by 1 pixel to the right and downward. This produces a border on the left and top of the image.

Expected results:

No border on the image

Comment 1

[BugBot [:suhaib / :marco/ :calixte]]

The Bugbug bot thinks this bug should belong to the 'Firefox::Screenshots' component, and is moving the bug to that component. Please revert this change in case you think the bot is wrong.

Comment 2

[Jeronimo Torti (Please send NI request to Brindusa Tot)]

Hi luke.leheny,
I tested this issue on Ubuntu20, on Firefox Nightly 97.0a1 (2021-12-09) (64-bit) version and Release 95.0 (64-bit), but I was unable to reproduce this issue on my end. Also, I'm not able to see the issue in the screenshot accurately.

Please, answer the following questions in order to investigate this issue further:

• Does this issue occur in the latest nightly version of firefox? Here is a link from where you can download it: https://www.mozilla.org/en-US/firefox/channel/desktop/

• If you are still able to reproduce it, please, share or add another screenshot and zoom the error or add another information you consider useful.

I let the assigned component in order to get the dev team involved.
'Firefox-Screenshots' team: if the component is not relevant please change it to a more appropriate one.

Regards,
Jerónimo.

Comment 3

[luke.leheny]

Attachment: image.jpg

Comment 4

[luke.leheny]

Hi Jeronimo,

Thanks for looking into it. I've attached another image with an example of the issue. The image is supposed to be entirely black with the play button in the top right. The problem is that the left edge of the image has a white border. The image was screenshotted on a page where the background is white, so either the screenshot tool added part of the background to the left side of the image, or the screenshot grabbed the image from 1 pixel to the right of where it was supposed to grab it.

I hope this makes more sense.

Thanks

Comment 5

[BugBot [:suhaib / :marco/ :calixte]]

The severity field is not set for this bug.
:sfoster, could you have a look please?

For more information, please visit auto_nag documentation.

Comment 6

[Sam Foster [:sfoster] (he/him)]

:niklas, are you actively working on this? Can you unassign if you don't expect to get to it this week.

I'd like to get all these kind of scaling and what-pixels-do-we-capture bugs ironed out in the extension if possible so we minimize the number of duplicate bugs and maintaining logic there and the component.

If we have reliable steps to reproduce, it would be great to add a test (in the component) for this.

Comment 7

[Niklas Baumgardner [:niklas]]

I looked into this a little bit but I didn't get anywhere with it. I don't think I will be able to get to it this week so I will unassign.

I can reproduce this error by

1. go to https://unsplash.com/
2. screenshot one of the images on unslpash
3. download or copy the image to view

The resulting image will have a border.

When I was debugging this I noticed that the screenshot pixel coordinates sometimes had decimals so this might be a rounding error with the decimal places. I wasn't able to confirm this though.