291667 2025-04-16 22:06:52 -0700 REGRESSION(288714@main): CanvasRenderingContext2D font with normal line height fails to parse 2025-05-15 12:43:22 -0700 1 1 1 Unclassified WebKit Canvas Safari 18 Mac (Apple Silicon) macOS 15 RESOLVED FIXED https://bugs.webkit.org/show_bug.cgi?id=285707 BrowserCompat, InRadar P2 Normal --- 1 wilson.louie sam ahmad.saleem792 ej.sefah karlcow koivisto sabouhallawa sam vitor.roriz webkit-bug-importer oldest_to_newest 2111447 0 wilson.louie 2025-04-16 22:06:52 -0700 Overview: Starting In Safari 18.4 (tested on macOS 15 Apple Silicon), when a font string containing a "normal" line-height value is set on the CanvasRenderingContext2D instance, it fails to parse. Getting the font value from the context just returns the default '10px sans-serif'. This was not a problem in prior Safari versions, such as 18.3.1 Steps to Reproduce: 1) Go to this reproducible test case: https://codepen.io/wlouie1/pen/qEEBMGa?editors=1111 2) Look at the console log. Compare them in Safari 18.4, prior Safari versions, and Chrome. Actual Results: As shown in the CodePen link: Set ctx.font = 'normal normal 400 normal 12px/normal Arial, Helvetica, sans-serif'; Log ctx.font: '10px sans-serif' Also as shown in the CodePen link, either omitting the "normal" line-height (which should be equivalent because it's the default line-height value) from the font string, or specifying any other line-height value, like 14px, works as expected. Logging ctx.font gives the expected '12px Arial, Helvetica, sans-serif' Chrome 135 or prior Safari versions correctly logs '12px Arial, Helvetica, sans-serif' for all 3 cases. Expected Results: Set ctx.font = 'normal normal 400 normal 12px/normal Arial, Helvetica, sans-serif'; Log ctx.font: '12px Arial, Helvetica, sans-serif' 2111471 1 ahmad.saleem792 2025-04-17 01:20:31 -0700 *** Safari Technology Preview 217 on macOS Sequoia *** " Set: normal normal 400 normal 12px/normal Arial, Helvetica, sans-serif Get: 10px sans-serif <------------------------------------------ bug " " Set: normal normal 400 normal 12px Arial, Helvetica, sans-serif Get: 12px Arial, Helvetica, sans-serif " " Set: normal normal 400 normal 12px/14px Arial, Helvetica, sans-serif Get: 12px Arial, Helvetica, sans-serif " *** Chrome Canary 137.0.7128.0 (Official Build) canary (arm64) *** " Set: normal normal 400 normal 12px/normal Arial, Helvetica, sans-serif Get: 12px Arial, Helvetica, sans-serif " " Set: normal normal 400 normal 12px Arial, Helvetica, sans-serif Get: 12px Arial, Helvetica, sans-serif " " Set: normal normal 400 normal 12px/14px Arial, Helvetica, sans-serif Get: 12px Arial, Helvetica, sans-serif " *** Firefox Nightly 139 (20250414211452) *** " Set: normal normal 400 normal 12px/normal Arial, Helvetica, sans-serif Get: 12px Arial, Helvetica, sans-serif " " Set: normal normal 400 normal 12px Arial, Helvetica, sans-serif Get: 12px Arial, Helvetica, sans-serif " " Set: normal normal 400 normal 12px/14px Arial, Helvetica, sans-serif Get: 12px Arial, Helvetica, sans-serif " _________ STP 217 is broken as well. 2111472 2 webkit-bug-importer 2025-04-17 01:21:05 -0700 <rdar://problem/149459999> 2111501 3 karlcow 2025-04-17 04:40:40 -0700 it looks like a parsing error in the code. pass 12px/20px pass 12px/12 fail 12px/a fail 12px/normal Canvas is using https://searchfox.org/wubkat/rev/5df2953b4ca7158afd166f3f8c130d1a8888cf0f/Source/WebCore/css/parser/CSSPropertyParserConsumer%2BFont.cpp#345-376 https://html.spec.whatwg.org/multipage/canvas.html#dom-context-2d-font > The font IDL attribute, on setting, must be parsed as a CSS <'font'> value (but without supporting property-independent style sheet syntax like 'inherit'), and the resulting font must be assigned to the context, with the 'line-height' component forced to 'normal', with the 'font-size' component converted to CSS pixels, and with system fonts being computed to explicit values. If the new value is syntactically incorrect (including using property-independent style sheet syntax like 'inherit' or 'initial'), then it must be ignored, without assigning a new font value. And > When the 'font-size' component is set to lengths using percentages, 'em' or 'ex' units, or the 'larger' or 'smaller' keywords, these must be interpreted relative to the computed value of the 'font-size' property of the font style source object at the time that the attribute is set I wonder if Safari is not right here (?) interpreting the spec. aka this part > If the new value is syntactically incorrect (including using property-independent style sheet syntax like 'inherit' or 'initial'), then it must be ignored, without assigning a new font value. 2112133 4 karlcow 2025-04-20 18:58:12 -0700 Wilson Thanks for the bug report Does it affect one of your products at Oracle? 2112323 5 wilson.louie 2025-04-21 18:45:32 -0700 (In reply to Karl Dubost from comment #4) > Wilson > Thanks for the bug report > > Does it affect one of your products at Oracle? Thanks Karl, yes, and we're currently working around it by omitting the "normal" line-height value from the font string. 2115439 6 sabouhallawa 2025-05-06 13:16:56 -0700 This is a regression of 288714@main. 2116304 7 sam 2025-05-10 11:09:20 -0700 Pull request: https://github.com/WebKit/WebKit/pull/45208 2116373 8 ews-feeder 2025-05-11 13:32:42 -0700 Committed 294767@main (3606cb0acd00): <https://commits.webkit.org/294767@main> Reviewed commits have been landed. Closing PR #45208 and removing active labels. 2117398 9 ews-feeder 2025-05-15 12:43:22 -0700 Committed 289651.520@safari-7621-branch (d5311fc7eb27): <https://commits.webkit.org/289651.520@safari-7621-branch> Reviewed commits have been landed. Closing PR #3090 and removing active labels.