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+..
+ This work is licensed under a Creative Commons Attribution 3.0 Unported
+ License.
+
+ http://creativecommons.org/licenses/by/3.0/legalcode
+
+================================
+Migration to Twitter Bootstrap 3
+================================
+
+https://blueprints.launchpad.net/fuel/+spec/tbs3
+
+Migrate from Twitter Bootstrap 2 (TB2) to Twitter Bootstrap 3 (TB3).
+
+
+Problem description
+===================
+
+Currently Fuel UI is based on TB2, which is not supported for more than a
+year. The current version of Twitter Bootstrap is 3.3.4. Also, our styles file
+(for TB2) is poorly structured as we haven't refactored it since the very
+beginning.
+
+
+Proposed change
+===============
+
+We should migrate to TB3 and reimplement Fuel UI markup according to Twitter
+Bootstrap changelog. Migrating to a newer version of Twitter Bootstrap is a
+great chance to reduce technical debt: we'll also have to reimplement all the
+styles.
+
+Migration can be done in a few steps:
+
+* Base layout markup (navbar, footer, page wrapper)
+* Simple pages (support page, login page, releases page, etc.)
+* Cluster page markup
+* Cluster page tabs
+* Nodes tab screens (disks, interfaces)
+* Dialogs
+
+Alternatives
+------------
+
+Migrate to some other HTML framework, though it doesn't makes much sense.
+
+Data model impact
+-----------------
+
+None.
+
+REST API impact
+---------------
+
+None.
+
+Upgrade impact
+--------------
+
+None.
+
+Security impact
+---------------
+
+None.
+
+Notifications impact
+--------------------
+
+None.
+
+Other end user impact
+---------------------
+
+As we're changing markup, we also can alter look of some features to match
+the new style.
+
+Performance Impact
+------------------
+
+There could be slight impact to performance of Fuel UI in browser as we
+overhaul the styles and markup, not sure if it get worse or better.
+
+Plugin impact
+-------------
+
+None.
+
+Other deployer impact
+---------------------
+
+None.
+
+Developer impact
+----------------
+
+Fuel UI contributors should be aware of the changelog of TB3 to efficiently
+write new code.
+
+Infrastructure impact
+---------------------
+
+None.
+
+
+Implementation
+==============
+
+Assignee(s)
+-----------
+
+Primary assignee:
+* Vitaly Kramskikh <vkramskikh@mirantis.com>
+
+Other contributors:
+* Alexandra Morozova <astepanchuk@mirantis.com>
+* Bogdan Dudko <bdudko@mirantis.com>
+* Julia Aranovich <jkirnosova@mirantis.com>
+* Kate Pimenova <kpimenova@mirantis.com>
+* Nikolay Bogdanov <nbogdanov@mirantis.com>
+
+Mandatory design review:
+* Vitaly Kramskikh <vkramskikh@mirantis.com>
+
+QA engineer:
+* Anastasia Palkina <apalkina@mirantis.com>
+
+Work Items
+----------
+
+As described in ``Proposed change`` section, though some changes could be more
+granular.
+
+
+Dependencies
+============
+
+None.
+
+
+Testing
+=======
+
+Existing functional test suite should be modified to support new markup.
+
+Acceptance criteria
+-------------------
+
+* New TB3-based markup is applied without any significant flaws (sizing and
+  layout issues).
+* Every existing UI feature works as it worked before, no missing information
+  or controls.
+
+
+Documentation Impact
+====================
+
+Screenshots of Fuel UI in the existing documentation should be updated.
+
+
+References
+==========
+
+* #fuel-ui on freenode