Reuploading the image here :-)

Add to current sprint per T321728: Preview font size has increased in Vector 2022

@TheresNoTime Since you stated that there might be a relation between this issue and T321728, I just wanted to inform you that I just noticed that I am experiencing the same problem as reported in the below quote. However, I am still not experiencing an increased font size in the "old school" preview which is the main issue at that page.

In T321728#8357205, @Zdzislaw wrote:

@Iniquity It doesn't just increase the preview font size. "This" change caused also the enlargement of all elements of the toolbox and the editor itself on pl wikisoource....

It looks like a "side effect" of T312963...

Confirmed on en.wikipedia.beta:

Manually negating out the inline defined

.vector-body {
	font-size: 100%;
}

lets the more reasonable

.vector-body {
	font-size: 0.875em;
	font-size: calc(1em * 0.875);
	line-height: 1.6;
}

apply, resulting in:

Turning off "Enable responsive mode" resolves this for me — @InsaneHacker can you confirm? If you turn off "Enable responsive mode" in your Special:Preferences, does the text size look the same? (for me it's 13px for the edit window, and 14px for the realtime preview)

In T322337#8368696, @TheresNoTime wrote:

Turning off "Enable responsive mode" resolves this for me — @InsaneHacker can you confirm? If you turn off "Enable responsive mode" in your Special:Preferences, does the text size look the same? (for me it's 13px for the edit window, and 14px for the realtime preview)

Not 'Enable limited width mode'? Because turning this setting off fixed this behavior :)

Oh, wrong task, sorry, this comment for T321728.

In T322337#8368696, @TheresNoTime wrote:

Turning off "Enable responsive mode" resolves this for me — @InsaneHacker can you confirm? If you turn off "Enable responsive mode" in your Special:Preferences, does the text size look the same? (for me it's 13px for the edit window, and 14px for the realtime preview)

Unfortunately not :-( – I tried turning off responsive mode, which didn't change anything. I then logged in via a Private Browsing window just in case there was some caching issue, but the text was still too large. I then experimented with turning off both responsive mode and limited width mode, turning both off, or just having one of either on, but I don't see any changes.

It looks like this in all cases:

In T322337#8368748, @InsaneHacker wrote:

In T322337#8368696, @TheresNoTime wrote:

Turning off "Enable responsive mode" resolves this for me — @InsaneHacker can you confirm? If you turn off "Enable responsive mode" in your Special:Preferences, does the text size look the same? (for me it's 13px for the edit window, and 14px for the realtime preview)

Unfortunately not :-( – I tried turning off responsive mode, which didn't change anything. I then logged in via a Private Browsing window just in case there was some caching issue, but the text was still too large. I then experimented with turning off both responsive mode and limited width mode, turning both off, or just having one of either on, but I don't see any changes.

On further investigation, that may have been me forgetting to turn off a style override — sorry, please ignore that bit of advice!

I've narrowed it down to this line (commenting that out does resolve it), but that was added by @Samwilson for a good reason.. hmm..

Change 853060 had a related patch set uploaded (by Samtar; author: Samtar):

[mediawiki/skins/Vector@master] skinStyles: Move mw-parser-output out of more specific selector

https://gerrit.wikimedia.org/r/853060

Test wiki created on Patch demo by TheresNoTime using patch(es) linked to this task:
https://patchdemo.wmflabs.org/wikis/21bb3fe9d6/w

Should probably split this out into it's own task, but I don't think previews are meant to look like this with the "Enable limited width mode" toggle unchecked...

In T322337#8368807, @TheresNoTime wrote:

Should probably split this out into it's own task, but I don't think previews are meant to look like this with the "Enable limited width mode" toggle unchecked...

It looks like the behaviour is actually inverted: when the pref is off the width is narrow, but when it's on then the preview is full-width. I've created T322385 for it.

Test wiki on Patch demo by TheresNoTime using patch(es) linked to this task was deleted:

https://patchdemo.wmflabs.org/wikis/21bb3fe9d6/w/

Change 853060 merged by jenkins-bot:

[mediawiki/skins/Vector@master] skinStyles: Move mw-parser-output out of more specific selector

https://gerrit.wikimedia.org/r/853060

it looks like the preview will indeed return to normal font size after this change, but the edit page descriptions, the toolbox and other elements are still displayed in the enlarged font size:

I've been experimenting with this, but can't seem to figure out how to ensure that #wikiPreview maintains font-size:100% (so its width matches the content width when not editing), while also keeping all other text within .vector-body at the smaller size.

Here's a striped-down example that tries to replicate the structure: https://codepen.io/freosam/pen/poKEGNo

Enable limited width mode	Reading	Editing	Normal preview	Live preview
On	width: 960px	width 1492px (without left-hand menu open), 1200px (with left-hand menu open)	width: 960px	width: 1492px (without left-hand menu open), 1200px (with left-hand menu open)
Off	width: 1802px (without TOC or left-hand menu), 1510px (with TOC or left-hand menu)	width: 1802px (without left-hand menu), 1510px (with left-hand menu)	width of content: 960px (with and without TOC or left-hand menu); width of WikiEditor: 1802px (without TOC or left-hand menu), 1510px (with TOC or left-hand menu)	width of content: 960px (with and without TOC or left-hand menu); width of WikiEditor: 1802px (without TOC or left-hand menu), 1510px (with TOC or left-hand menu)

All the above was tested at 100% zoom and Firefox's default font size setting (16px).

The font size of the article's content was always 14px. Other elements on the page were 16px (raised as T322738).

Test environment: https://en.wikipedia.beta.wmflabs.org MediaWiki 1.40.0-alpha (02a97c8) 10:21, 9 November 2022. Vector 1.0.0 (32230c1) 08:01, 9 November 2022. WikiEditor 0.5.3 (c621738) 07:59, 9 November 2022.
Test browser: Firefox 91.

@Samwilson , @dom_walden @TheresNoTime
After the change introduced here, the preview (in the vector-2022 skin) reverted to the standard font size in the main space,
but on Wikisource in the "Page" NS it made that (in the preview) unfortunately the font size is too small(!) (
(left view; right: preview):

much smaller than before the font enlargement that this change was supposed to eliminate :(

This makes it very difficult to work on WS

In T322337#8406969, @Zdzislaw wrote:

@Samwilson , @dom_walden @TheresNoTime
After the change introduced here, the preview (in the vector-2022 skin) reverted to the standard font size in the main space,
but on Wikisource in the "Page" NS it made that (in the preview) unfortunately the font size is too small(!) (

Thanks for raising this. I think the problem is it has two nested <div class="mw-parser-output">, which means font-size: 0.875em is applied twice.

I raised T323751.