1724518 - When displaying the contents of the web page, the letters are superimposed on each other.

Status: NEW

(Core :: Web Painting, defect, P3)

Description

[Danax]

Attachment: The superimposed letters are underlined.

User Agent: Mozilla/5.0 (Windows NT 6.1; rv:90.0) Gecko/20100101 Firefox/90.0

Steps to reproduce:

I go to the web page https://resh.edu.ru/subject/lesson/4225/main/288082/

Then I click on rectangles. Rectangles turn over. There are texts on their reverse side.

Actual results:

The letters of the text parts are superimposed on each other so that it is impossible to read.

However, everything is fine in Chrome.

Expected results:

The text should be readable.

Comment 1

[Danax]

Alice0775 White What do you want to tell by your message?

Comment 2

[Alice0775 White]

(In reply to Danax from comment #1)

Alice0775 White What do you want to tell by your message?

I think this bug is related to the layout engine. So, first of all, I changed the category so that it would get the attention of the core developers.

Comment 3

[Emilio Cobos Álvarez (:emilio)]

Thanks! This seems related to backface-visibility: hidden, which is a graphics feature.

Seems like this never worked (or at least I tried 68 and 78 and behavior is the same.

It seems the element they apply backface-visibility: hidden to is not transformed, so we don't honor it. If I add transform: scale(1); to that element, then it works. Matt, do you know off-hand who's right here?

Comment 4

[Danax]

You're right. The problem is in the background. I thought that the letters of the text string are superimposed. In fact, this is the visible text from the reverse side. In another place, the mirror reflected text from the reverse side is clearly visible: https://resh.edu.ru/subject/lesson/6476/main/178256/

Comment 5

[Matt Woodrow (:mattwoodrow)]

With the current spec, we're correct, since backface-visibility hides the backface of the element, and the text is a separate (descendant) element which doesn't have its backface hidden.

As shown here though, that's generally not the behaviour that people expect though.

Dbaron is currently investigating this and hopefully we can get the spec changed so that backface-visibility creates a stacking context (like adding transform does), so that the property hides the element and all of its descendants.

Comment 6

[Emilio Cobos Álvarez (:emilio)]

Thanks Matt :)