Paste from Excel doesn't preserve styles

[msamsel]

Type of report

Bug

Provide detailed reproduction steps (if any)

1. Open excel: simple_styles.xlsx
2. Copy blue table
3. Paste it in Chrome

Expected result

The background color of the table will be preserved

Actual result

The table is copied without background color

Other details

Issue doesn't occur on 4.12.1

• Browser: Edge/Chrome
• OS: Windows10
• CKEditor version: 4.13.0
• Installed CKEditor plugins: …

[Comandeer]

It seems that content from Excel is not recognized as Office content and therefore Paste from Word skips parsing it. It also causes #3585 and #3625 even when PfW is enabled.

Probably issue is connected with simplified logic for getting pasted HTML.

Current version:

ckeditor4/plugins/pastefromword/plugin.js

Line 77 in 42ff73a

mswordHtml = data.dataValue,

Previous version:

ckeditor4/plugins/pastefromword/plugin.js

Lines 64 to 71 in 64749bb

	dataTransferHtml = CKEDITOR.plugins.clipboard.isCustomDataTypesSupported ?
	data.dataTransfer.getData( 'text/html', true ) : null,
	// Required in Paste from Word Image plugin (#662).
	dataTransferRtf = CKEDITOR.plugins.clipboard.isCustomDataTypesSupported ?
	data.dataTransfer.getData( 'text/rtf' ) : null,
	// Some commands fire paste event without setting dataTransfer property. In such case
	// dataValue should be used.
	mswordHtml = dataTransferHtml || data.dataValue,

[msamsel]

@Comandeer AFAIR from work on PFLO. data.dataValue doesn't contain meta tags, there's only body section of a clipboard.
I spot it during work on PFLO and also improve it, as this approach also generated issues for me when both PFLO and PFW was present in editor's config.
https://github.com/ckeditor/ckeditor4/pull/3624/files#diff-9609bf210ad60faf5b8f8f446baf4e1eR77-R83

[f1ames]

Fixed with 2f7937f.