importcss plugin causes javascript hang, misplacement of formats menu

[TinyMCE-User]

Description of problem:
The importcss plugin causes a javascript hang and the Formats menu contents get misplaced. See attached screen shot. It may be because content_css has 5 CSS files. I added 'preview_styles: false' but it didn't help.

Steps to reproduce:

1. add 'importcss' as a plugin
2. add 'styleselect' as toolbar item
3. add several CSS files to 'content_css'
4. load tinyMCE4 and click the Formats menu

Expected result:
Pulldown menu rendered in the Formats menu.

Actual result:
Pulldown menu rendered below TinyMCE, not connected visually.
Javascript hang.
Firefox warning prompt to stop unresponsive scripts.

Legacy information imported from TinyMCE bug tracker:

#T6242 posted by giulio

Tags: [firefox importcss javascript]
Status: Closed
Resolution: Fixed
Attached URL: none

[TinyMCE-User]

Need steps to reproduce this. Might be a large CSS file, circular references or similar. Please attach a working example where this is happening. Thanks

Posted by spocke

[TinyMCE-User]

Here is the working example of the issue: http://filtasystems-com.chiefinternetmarketer.net/tiny4test.cfm
It's loading 5 css files. About 18,000 lines of CSS.

Posted by giulio

[TinyMCE-User]

Optimized it a bit. Added a new importcss_file_filter option that allows you to exclude bootstrap etc. Works a lot better now.

Posted by spocke