Minimize / Restore / Close button is on unnatural position.

HiSky 

This problem is fixed now in the latest canary update version 85.0.543.0:

The size of buttons is now same as standard UWP Windows 10 apps and other Chromium browsers.

HiSky   For what it is worth, I found one version of Chromium for Linux (a build for Fedora) that seems to have worked out a way to get the vertical alignment correct:

Let's hope that Microsoft will do the same in Edge Chromium.  The misalignment is a rookie design/coding mistake, and I'm surprised that it hasn't already been corrected somewhere along the line by The Chromium Project or Google.   Google Chrome moved from two blocks to a single split block in 2015 or 2016 at the latest, based on screenshots I've found of Chrome in various iterations.

I think I see what you're saying. Those three buttons on the top right side of Edge should be a drop lower or centered to scale in the middle between the top and bottom of the bar. I compared it side by side vs Chromium and against my Windows 10 task bar (I keep my task bar on top of the screen due to running Open Shell/Classic Shell):

Edge Canary vs Chromium :

Edge Against Task bar:

Chromium Against Task bar:

HiSky    I think that I figured out what is going on.

First, a refinement of the screenshot used in an earlier comment, this time showing horizontal block in which the Minimize/Windowed/Close buttons are located, with the bottom of the block underlined in red and the center line shown in blue:

Second, a screenshot of the Minimize/Windowed/Close buttons in Edge Chromium shown in relationship to the tab bar, immediately to the left of the buttons, again showing the bottom of the block in red and the center line in blue:

And finally, a screenshot comparing Edge Chromium Dev Version 78.0.268.3 and Linux Chromium Version 76.0.3809.100 (Ubuntu Official Build):

Note the difference between Edge Chromium and Linux Chromium.   Linux Chromium uses two horizontal blocks, one for the Minimize/Windowed/Close buttons and another for the tabs.  Edge Chromium (and also, I believe based on your screenshots, Google Chrome) for Windows compresses the two blocks into one in order to conform to Windows 10 design protocols, splitting the block between the two functions, right and left. 

For whatever reason (probably inattentive coding), the Minimize/Windowed/Close buttons do not center vertically in the portion of the horizontal block assigned to them in either Google Chrome or Edge Chromium.  The issue also appears in other Chromium-based Windows browsers (e.g. Brave) that compress the tab block and the Minimize/Windowed/Close buttons into a single horizontal block.

It seems to me that Microsoft should treat this as a bug and fix it.

Here is an interesting finding of my own that the buttons are close to File Explorer ones

Edge C

Windows Explorer

PS: Yes I know my image subtitle for File Explorer is Windows Explorer

HiSky 

Edge insider Canary

Google Chrome Canary

In Edge, the buttons look like they need to be moved a little downwards but that's only when you compare it to the Google Chrome.

neither of the browsers have their buttons at the center, neither vertically nor horizontally. their buttons are way too close to the top. 

HiSky  Good catch.  It is subtle, but the buttons are not centered vertically in the allotted horizontal bar in Edge Chromium.  In addition to the comparison to Chrome, these are the comparisons to Edge (Classic) and Firefox:

I don't know it the difference is intentional, but it seems to me that vertical centering would be preferable to the offset.