Update to 2.0.4 '@checkout-tooltip-icon__font-size is undefined' error, no custom CSS load

[chloeefr]

Steps to reproduce

Using custom theme with Magento/blank as parent, working fine before recent update.

1. Updated to 2.0.4 using Composer
2. Cleared pub/static/frontend & var folders
3. Grunt watch

Expected result

Custom theme css load ok and continue working.

Actual result

1. "NameError: variable @checkout-tooltip-icon__font-size is undefined" error appearing twice at top of page.
2. No styling from custom theme loading.
3. When defining '@checkout-tooltip-icon__font-size is undefined' in _extends.less in blank theme, a different "NameError: variable" shows.

[ktomk]

IIRC from work, this issue could have happened already in 2.0.2, not 2.0.4 only. I've not checked if there are earlier reports. This is also not limited to CE edition.

[undefined-olha]

@chloeefr, thank you for reporting this issue. Internal MAGETWO-52100 ticket has been created.

[undefined-olha]

@chloeefr, could you please check if this folder is not overwritten in your custom theme? Especially this this file which contains mentioned variable. Or could you please provide the structure of your project? I cannot reproduce the issue so far.

[MomotenkoNatalia]

Closing the issue as it cannot be reproduced and there is no response has been received from the reporter.
@chloeefr please feel free to reopen if you feel that issue could be reproduced.