Cool Chrome DevTools tips and tricks you wish you knew already

March 21, 2018 0 Comments

Cool Chrome DevTools tips and tricks you wish you knew already

 

 

Check out my overview of Chrome DevTools if you’re new to them

In the Elements panel, you can drag and drop any HTML element and change its position across the page

Drag-and-drop in the Elements panel

Select a node in the Elements panel, and type $0 in the console to reference it.

If you’re using jQuery, you can enter $($0) to access the jQuery API on this element.

Reference the currently selected element in the Console

Use $_ to reference the return value of the previous operation executed in the Console

Use the value of the last operation in the Console

In the Elements panel there are two super useful buttons.

The first lets you add a new CSS property with any selector you want, but pre-filling the currently selected element:

Add CSS rules

The second one lets you trigger a state for the selected element, so you can see the styles applied when it’s active, hovered, or on focus.

Edit the element state

Click the name of the CSS file that you edited. The inspector opens it into the Sources pane, and from there you can save it with the live edits you applied.

This trick does not work for new selectors added using +, or into the element.style properties, but only for modified, existing ones.

Save to file the modified CSS

Select an element and press cmd-shift-p (or ctrl-shift-p in Windows) to open the Command Menu, and select Capture node screenshot

Screenshot a single element

Pressing cmd-f (ctrl-f in Windows) opens the search box in the Elements panel.

You can type any string in there to match the source code, or you can also use CSS selectors to have Chrome generate an image for you:

Find an element using CSS selectors

To write commands that span over multiple lines in the Console, press shift-enter.

Once you’re ready, press enter at the end of the script to execute it:

Shift-enter in the Console to write multiline commands

You can clear the console using the Clear button on the top-left of the console, or by pressing ctrl-l or cmd-k.

In the Sources panel:

  • cmd-o (ctrl-o in Windows), shows all the files loaded by your page.
  • cmd-shift-o (ctrl-shift-o in Windows) shows the symbols (properties, functions, classes) in the current file.
  • ctrl-g goes to a specific line.
Go to file

Instead of writing again and again a variable name or an expression you are going to check a lot during a debug session, add it to the Watch Expression list.

Watch Expression

From the debugger open the XHR/Fetch Breakpoints panel.

You can set it to break any time an XHR/Fetch call is sent, or just on specific ones:

XHR/Fetch debugging

Right-click an element and enable Break on Subtree Modifications. Whenever a script traverses that element’s children and modifies them, the debugger stops automatically to let you inspect what’s happening.

Debug on DOM modifications

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Originally published at flaviocopes.com.


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