Apart from testing in actual browsers, and occasional use of the document inspector on OTHER people's code, I try NOT to over-rely on tools or even use extra ones in the first place. When I do it's almost ALWAYS to deal with some mess someone else built as for me, most such stuff just gets in the damned way.
There is FAR too much reliance on tools and not enough on what's between people's ears these days; made all the sadder by the fact that so many tools... well, what was it Dan Schulz (RIP) said on the topic?
The only thing about Dreamweaver that can be considered professional grade tools are the people promoting its use!
... a sad but true state of affairs. Far, FAR too often these days you'll hear "this tool made it easier" or "this framework made it simpler" when the only real fact to be found is that the person saying it didn't know enough about the underlying languages or technologies to even know if what they just said was true, much less even be working on the task at hand!
STOP over-relying on pointless tools and get your damned brain working on the problem! Even better, try to develop good habits that you can fall back on when mental stress or the task overwhelms you.
I'll stack experience, brainpower, and good ingrained habits over any automated tool any day of the week. Much like how idols are for the addle-minded, most 'tools' are for fools -- at least when talking anything more than the most basic needed to do the job.
ALL the browsers you can possibly test in, properly configured testing server, flat text editor that allows multiple separate windows per open file, DONE!