User-Agent: Mozilla/5.0 (Macintosh; U; PPC Mac OS X Mach-O; en-US; rv:1.8.0.3) Gecko/20060426 Firefox/1.5.0.3 Build Identifier: Mozilla/5.0 (Macintosh; U; PPC Mac OS X Mach-O; en-US; rv:1.8.0.3) Gecko/20060426 Firefox/1.5.0.3 If the strokeStyle attribute of a canvas drawing context is set to a color that includes an alpha channel, it contains an illegal value when read back. For example, setting the strokeStyle to 'rgba(0, 0, 255, 0.5)' will cause it to be read back as 'rgb(0, 0, 255, 0.50)'. If the strokeStyle is set to this illegal value, it results in a Javascript exception. Reproducible: Always Steps to Reproduce: var canvas = document.getElementById("canvas"); var ctx = canvas.getContext("2d"); ctx.strokeStyle = 'rgba(0, 0, 255, 0.5)'; ctx.strokeStyle = ctx.strokeStyle; Actual Results: Recieved the following Javascript exception (using Firebug): uncaught exception: [Exception... "Component returned failure code: 0x80070057 (NS_ERROR_ILLEGAL_VALUE) [nsIDOMCanvasRenderingContext2D.strokeStyle]" nsresult: "0x80070057 (NS_ERROR_ILLEGAL_VALUE)" location: "JS frame :: file:///Users/colin/Desktop/canvasbug.html :: <TOP_LEVEL> :: line 16" data: no] Expected Results: The strokeStyle should have been read back as the same value that had been set earlier.

This produces the Javascript exception mentioned above.

WFM in current trunk and 1.8 branch.

Vlad fixed this in the patch for bug 333613. *** This bug has been marked as a duplicate of 333613 ***