CSS display Property.

Value Description
inline Default value. Displays an element as an inline element (like <span>)
block Default value. Displays an element as an inline element (like <span>)
flex Displays an element as an block-level flex container. New in CSS3
inline-block Displays an element as an inline-level block container. The inside of this block is formatted as block-level box, and the element itself is formatted as an inline-level box
inline-flex Displays an element as an inline-level flex container. New in CSS3
inline-table The element is displayed as an inline-level table
list-item Let the element behave like a <li> element
run-in Displays an element as either block or inline, depending on context
table Let the element behave like a <table> element
table-caption Let the element behave like a <caption> element
table-header-group
Let the element behave like a <colgroup> element
table-header-group Let the element behave like a <thead> element
table-row Let the element behave like a <tr> element
none The element will not be displayed at all (has no effect on layout)
table-footer-group  Let the element behave like a <tfoot> element
table-row-group  Let the element behave like a <tbody> element
initial Sets this property to its default value.
inherit Inherits this property from its parent element.

How to remove us.search.yahoo tab hijack in Firefox?

To solve us.search.yahoo tab hijack problem, you have to follow this steps:

  1. In the Location bar, type about:config and press Enter. The about:config “This might void your warranty!” warning page may appear.
  2. Click I’ll be careful, I promise! to continue to the about:config page.
  3. copy from here the next : browser.newtab.url , and paste it in the search area
  4. right-click on it, select modify and write whatever you want (for example google.com)
  5. click ok, exit firefox and restart it.

see for more info : New Tab Page – show, hide and customize top sites