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## Summary of the Pull Request
Spec for #3062
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## PR Checklist
* [ ] Closes #xxx
* [x] CLA signed. If not, go over [here](https://cla.opensource.microsoft.com/microsoft/Terminal) and sign the CLA
* [ ] Tests added/passed
* [x] Is documentation
* [ ] Schema updated.
* [x] I work here
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## Detailed Description of the Pull Request / Additional comments
Read the spec
### ⇒ [doc link](https://github.com/microsoft/terminal/blob/dev/migrie/s/5000/doc/specs/%235000%20-%20Process%20Model%202.0/%235000%20-%20Process%20Model%202.0.md) ⇐
## Summary of the Pull Request
This spec is _exceptionally long_, and is currently a work in progress. There are a few more things I'd like to have experimentally verified (though, I'm fairly certain they _will_ work, with the right combination of flags and such). Additionally, a few sections have remaining TODOs before the spec is finished. However, this spec is already fairly long, and I want to give people as much time to get their eyes on it as possible.
### Abstract
>
> The Windows Terminal currently exists as a single process per window, with one
> connection per terminal pane (which could be an additional conpty process and
> associated client processes). This model has proven effective for the simple
> windowing we've done so far. However, in order to support scenarios like
> dragging tabs into other windows, or having one top-level window with different
> elevation levels within it, this single process model will not be sufficient.
>
> This spec outlines changes to the Terminal process model in order to enable the
> following scenarios:
>
> * Tab Tearoff/ Reattach ([#1256])
> * Run `wt` in the current window ([#4472])
> * Single Instance Mode ([#2227])
> * Quake Mode ([#653])
> * Mixed Elevation ([#1032] & [#632])
## PR Checklist
* [x] Specs: #5000
* [x] References: #1256, #4472, #2227, #653, #1032, #632, #492
* [x] I work here
## Detailed Description of the Pull Request / Additional comments
_\*<sup>\*</sup><sub>\*</sub> read the spec <sub>\*</sub><sup>\*</sup>\*_
### Plurals and paste tenses
In the past, plurals `foo`+`s` and past tenses `foo`+`ed` were
automatically tolerated. This turned out to be a bad design choice on my
part.
The basic example is that `potatos` would sometimes be treated as a
mistake and sometimes not (depending on the presence of `potato`).
You can see in this PR, that this logic resulted in `Applys` being
accepted as a word along with `AppContainered` -- there's nothing
intrinsically wrong w/ the latter, but unfortunately in order to screen
out the former, my shortcut just couldn't stick around. This means that
the `dictionary`/`expect` files will grow perhaps by a tiny bit, but as
you can see, not really by much.
This is also why `thereses` (a user) was accepted as a word in the past
(therese is in the base dictionary, so `therese` + `s` was acceptable).
### Pull requests
When GitHub initially introduced GitHub Actions, the event for
`pull_request` was created without enough permission for a tool like
this to work properly. I worked around that by using the `schedule`
event. In 2020, they introduced a replacement event
`pull_request_target` which has enough permission. This means that I can
stop relying on the `schedule` event.
### Miscellaneous
* I've folded together some `expect/` files since now is as good a time
as any.
* I've included a hint about `excludes.txt` (I added a similar one for
our primary repo recently, and it came up this week in
`microsoft/terminal` -- @zadjii-msft)
* I've standardized on a default of `.github/actions/spelling` to make
the out of the box experience easier for new adopters, so I'm applying
that change here -- if you're attached to the old directory name,
specifying it is still supported. -- note the directory rename may
cause a merge conflict for people with open PRs and changes to the
contents, this shouldn't be a big problem.
