Bug 28866 – when you add a new css rule via the web inspector, reload the page, and try again it will not work

• Component: Web Inspector (Deprecated)
• Status: RESOLVED WORKSFORME

in the CSS part of the web inspector, when you click the "Double-Click to add"  and add a new style (say: "body p") and set color:red then reload the page and do the exact same thing, it does not work.

In comment https://bugs.webkit.org/show_bug.cgi?id=27124#c13 Timothy Hatcher says this:

I think what is happeneing here is that we have a reference to the style
element we created for the previous page still, so we think we don't need to
make a new one and just append to the old one in the previous page.

This reference should be cleared in the ElementsPanel reset method.

for more info see:
comment 12 and 13 of
https://bugs.webkit.org/show_bug.cgi?id=27124

[Joseph Pecoraro]

We do still have a reference to the style element, which needs to be cleared:

    delete InjectedScript.stylesheet;

However, there is no safe place to clear this.  The ElementPanel's constructor does not appear to get rerun on a refresh, only reset(). However, reset() gets called all over the place and making new stylesheets would lose access to deleting old rules.  I have a similar problem with Cookies in the StoragePanel which I alluded to in Bug 27202.

I propose adding a hook for panels names something like "onpageload" or "onrefresh".  The idea being (correct me if I am wrong):

  - A Panel's Constructor is run once when the Inspector is first opened
  - populateInterface() is run when ...?
  - reset() is called all over the place without knowledge of new pages
  - onpageload() would be called on navigation (including page refresh)

onpageload() plugs the hole of wanting to do something once per page load such as:

  - Wiping (or Creating) the Injected Stylesheet
  - Adding the Cookies Tree Element once, because it need only be made once

Uglier, but still usable would be providing a flag to reset like reset(isPageLoad) which could be made true on new page loads.

[Timothy Hatcher]

I guess reset does serve to purposes. It is called when the page loads and when the Inspector is closed. Spliting this into two functions would be fine, but I think the flag on reset is good too.

[Nikita Vasilyev]

Looks like the bug has been fixed by https://bugs.webkit.org/show_bug.cgi?id=27124 (or something else). I can't reproduce it.