The following three ABC code samples should be equivalent:

X:0         X:0            X:0
K:C bass    K:Cmaj bass    K:C major bass
A,,B,,C,    A,,B,,C,       A,,B,,C,

However, the first image displays incorrectly if it has been previously displayed and cached by the browser.

To reproduce, if the image immediately below looks correct, reload the page, and it produces the image at the bottom of this post.

X:0
K:C bass
A,,B,,C,

Whereas the other two both render correctly regardless whether they were previously cached, as follows.

X:0
K:C major bass
A,,B,,C,

The incorrect image looks like this.

Reproduced on

Widows 10 (v. 2004) with

• Chrome 85.0.4183.121 (on 2 machines)
• Edge 85.0.564.63
• Firefox 81.0 (on 2 machines; clean install. Behavior is different, however. First time opening page, display incorrect. Okay on refresh.)

MacOS 10.15.7 with

• Chrome 85.0.4183.121
• Safari 14.0

See end of post for workaround

The following three ABC code samples should be equivalent:

X:0         X:0            X:0
K:C bass    K:Cmaj bass    K:C major bass
A,,B,,C,    A,,B,,C,       A,,B,,C,

However, the first image displays incorrectly if it has been previously displayed and cached by the browser.

To reproduce, if the image immediately below looks correct, reload the page, and it produces the image at the bottom of this post.

X:0
K:C bass
A,,B,,C,

Whereas the other two both render correctly regardless whether they were previously cached, as follows.

X:0
K:C major bass
A,,B,,C,

The incorrect image looks like this.

Reproduced on

Widows 10 (v. 2004) with

• Chrome 85.0.4183.121 (on 2 machines)
• Edge 85.0.564.63
• Firefox 81.0 (on 2 machines; clean install. Behavior is different, however. First time opening page, display incorrect. Okay on refresh.)

MacOS 10.15.7 with

• Chrome 85.0.4183.121
• Safari 14.0

WORKAROUND

Reload the page with a cache bypass. On Windows this is generally done with CTRL+F5; on MacOS, CMD+SHIFT+R.

The following three ABC code samples should be equivalent:

X:0         X:0            X:0
K:C bass    K:Cmaj bass    K:C major bass
A,,B,,C,    A,,B,,C,       A,,B,,C,

However, the first image displays incorrectly if it has been previously displayed and cached by the browser.

To reproduce, if the image immediately below looks correct, reload the page, and it produces the image at the bottom of this post.

X:0
K:C bass
A,,B,,C,

Whereas the other two both render correctly regardless whether they were previously cached, as follows.

X:0
K:C major bass
A,,B,,C,

The incorrect image looks like this.

The following three ABC code samples should be equivalent:

X:0         X:0            X:0
K:C bass    K:Cmaj bass    K:C major bass
A,,B,,C,    A,,B,,C,       A,,B,,C,

However, the first image displays incorrectly if it has been previously displayed and cached by the browser.

To reproduce, if the image immediately below looks correct, reload the page, and it produces the image at the bottom of this post.

X:0
K:C bass
A,,B,,C,

Whereas the other two both render correctly regardless whether they were previously cached, as follows.

X:0
K:C major bass
A,,B,,C,

The incorrect image looks like this.

Reproduced on

Widows 10 (v. 2004) with

• Chrome 85.0.4183.121 (on 2 machines)
• Edge 85.0.564.63
• Firefox 81.0 (on 2 machines; clean install. Behavior is different, however. First time opening page, display incorrect. Okay on refresh.)

MacOS 10.15.7 with

• Chrome 85.0.4183.121
• Safari 14.0

The following three ABC code samples should be equivalent:

X:0         X:0            X:0
K:C bass    K:Cmaj bass    K:C major bass
A,,B,,C,    A,,B,,C,       A,,B,,C,

However, the first does not render correctly.

X:0
K:C bass
A,,B,,C,

Whereas the other two both render correctly, as follows.

X:0
K:C major bass
A,,B,,C,

EDIT: The incorrect rendering appears to be platform/browser specific. On Win10/Chrome85.0.4183.102, I see

However on Win10/Edge and on my iPad, I see the correct rendering.

The following three ABC code samples should be equivalent:

X:0         X:0            X:0
K:C bass    K:Cmaj bass    K:C major bass
A,,B,,C,    A,,B,,C,       A,,B,,C,

However, the first image displays incorrectly if it has been previously displayed and cached by the browser.

To reproduce, if the image immediately below looks correct, reload the page, and it produces the image at the bottom of this post.

X:0
K:C bass
A,,B,,C,

Whereas the other two both render correctly regardless whether they were previously cached, as follows.

X:0
K:C major bass
A,,B,,C,

The incorrect image looks like this.