please add Glyphicons icon fonts as in the version 3.3.5 which is best to use an appropriate icon easily while it's not available in v4-alpha. I think its necessary and i recommend to add in v4 bootstrap. and tooltip in v4 is not working, please check.
icon fonts pose problems out of the box - see https://speakerdeck.com/ninjanails/death-to-icon-fonts
the v4 migration guide includes information on how authors can still easily add their own icon fonts if they so wish.
and tooltip problem is a dupe of #17097
Glyphicons were deliberately dropped in v4; see http://v4-alpha.getbootstrap.com/migration/#components
Lots of folks were already using other icon fonts (e.g. Font Awesome) instead of Glyphicons with Bootstrap v3 anyway. Unbundling Glyphicons lets those folks avoid duplication in their projects.
i know glyphicons dropped in v4. So, what's the alternate of this? also refer a other icon font tutorial.
you add them yourself... 8b4925f - all these other icon font sites offer some fairly simple explanations on how their fonts can be used, so no point in duplicating anything of the sort in Bootstrap's docs.
@msbg93 I'd recommend reading https://fortawesome.github.io/Font-Awesome/get-started/ which does a good job of providing examples for possible workflows to integrate (their) icon font with a project. While this is specific to them, the general steps to integrate with a project should be very similar unless a very unique environment is in use. Hope this helps!