bootstrap v2, used by toaster, is licensed under Apache-2.0. They ended up having to relicense it as projects that were GPLv2 could not use it, so bootstrap > 2 is now MIT which is GPLv2 compatible. For information on the issue see: https://github.com/twbs/bootstrap/issues/2054
One way to do this (and probably the least amount of work, perhaps?) is to revert https://github.com/twbs/bootstrap/pull/11927 and work the MIT licensed replacement code at https://github.com/twbs/bootstrap/pull/11928 into toaster. This would essentially fork bootstrap into an MIT licensed fork. I've not looked at the technical merits of this, but from a license compliance standpoint, it would unblock us.
updated to bootstrap V3 in 2.2 M1.
checking that bootstrap v3 is present in 2.2 M1 libby@liberta1-MOBL1:~/Toaster2.2_M1/poky$ git log | head -1 commit 6f0c5537e02c59e1c8f3b08f598dc049ff8ee098 libby@liberta1-MOBL1:~/Toaster2.2_M1/poky$ libby@liberta1-MOBL1:~/Toaster2.2_M1/poky$ git grep bootstrap bitbake/lib/toaster/toastergui/static/css/bootstrap.css: * Bootstrap v3.3.6 (http://getbootstrap.com) bitbake/lib/toaster/toastergui/static/css/bootstrap.css: * Licensed under MIT (https://github.com/twbs/bootstrap/blob/master/LICENSE) bitbake/lib/toaster/toastergui/static/css/bootstrap.css:/*# sourceMappingURL=bootstrap.css.map */ bitbake/lib/toaster/toastergui/static/css/bootstrap.css.map:{"version":3,"sources":["bootstrap.css","less/normalize.less","less/print.less","less/glyphicons.less","less/scaffolding.less","less/mixins/vendor-prefixes.less","less/mixins/tab-focus.less","less/mixins/image.less","less/type.less","less/mixins/text-emphasis.less","less/mixins/background-variant.less","less/mixins/text-overflow.less","less/code.less","less/grid.less","less/mixins/grid.less","less/mixins/grid-framework.less","less/tables.less","less/mixins/table-row.less","less/forms.less","less/mixins/forms.less","less/buttons.less","less/mixins/buttons.less","less/mixins/opacity.less","less/component-animations.less","less/dropdowns.less","less/mixins/nav-divider.less","less/mixins/reset-filter.less","less/button-groups.less","less/mixins/border-radius.less","less/input-groups.less","less/navs.less","less/navbar.less","less/mixins/nav-vertical-align.less","less/utilities.less","less/breadcrumbs.less","less/pagination.less","less/mixins/pagination.less","less/pager.less","less/labels.less","less/mixins/labels.less","less/badges.less","less/jumbotron.less","less/thumbnails.less","less/alerts.less","less/mixins/alerts.less","less/progress-bars.less","less/mixins/gradients.less","less/mixins/progress-bar.less","less/media.less","less/list-group.less","less/mixins/list-group.less","less/panels.less","less/mixins/panels.less","less/responsive-embed.less","