I tried to evaluate php tools with Visual Studio:
Microsoft Visual Studio Professional 2019 Version 16.5.2
on Microsoft Windows 10 Enterprise Version 10.0.17134 Build 17134
Neither PHP tools 1.40.12103 nor 1.40.12223 will start.
ActivityLog:
<entry>
<record>764</record>
<time>2020/11/03 11:21:14.415</time>
<type>Information</type>
<source>VisualStudio</source>
<description>Begin package load [ComposerPackage]</description>
<guid>{52323E24-8E37-4959-B894-8BA2026BFBC4}</guid>
</entry>
<entry>
<record>765</record>
<time>2020/11/03 11:21:14.423</time>
<type>Error</type>
<source>VisualStudio</source>
<description>SetSite failed for package [ComposerPackage]Source: 'Devsense.VisualStudio.Composer' Description: Could not load file or assembly 'Microsoft.VisualStudio.Threading, Version=16.6.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a' or one of its dependencies. The system cannot find the file specified.
System.IO.FileNotFoundException: Could not load file or assembly 'Microsoft.VisualStudio.Threading, Version=16.6.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a' or one of its dependencies. The system cannot find the file specified.
File name: 'Microsoft.VisualStudio.Threading, Version=16.6.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a'
 at Devsense.VisualStudio.Composer.ComposerPackage.InitializeAsync(CancellationToken cancellationToken, IProgress`1 progress)
 at Microsoft.VisualStudio.Shell.AsyncPackage.<>c__DisplayClass20_0.<<Microsoft-VisualStudio-Shell-Interop-IAsyncLoadablePackageInitialize-Initialize>b__1>d.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
 at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
 at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
 at Microsoft.VisualStudio.Threading.JoinableTask.<JoinAsync>d__68.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
 at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
 at Microsoft.VisualStudio.Services.VsTask.RethrowException(AggregateException e)
 at Microsoft.VisualStudio.Services.VsTask.InternalGetResult(Boolean ignoreUIThreadCheck)
 at Microsoft.VisualStudio.Services.VsTask.GetResult()

WRN: Assembly binding logging is turned OFF.
To enable assembly bind failure logging, set the registry value [HKLM\Software\Microsoft\Fusion!EnableLog] (DWORD) to 1.
Note: There is some performance penalty associated with assembly bind failure logging.
To turn this feature off, remove the registry value [HKLM\Software\Microsoft\Fusion!EnableLog].
</description>
<guid>{52323E24-8E37-4959-B894-8BA2026BFBC4}</guid>
<hr>80070002</hr>
<errorinfo></errorinfo>
</entry>
<entry>
<record>766</record>
<time>2020/11/03 11:21:14.439</time>
<type>Error</type>
<source>VisualStudio</source>
<description>End package load [ComposerPackage]</description>
<guid>{52323E24-8E37-4959-B894-8BA2026BFBC4}</guid>
<hr>80070002</hr>
<errorinfo></errorinfo>
</entry>
<entry>
<record>767</record>
<time>2020/11/03 11:21:14.831</time>
<type>Information</type>
<source>UserConnection</source>
<description>user authentication successful for IDE user</description>
</entry>
<entry>
<record>768</record>
<time>2020/11/03 11:21:15.260</time>
<type>Information</type>
<source>VisualStudio</source>
<description>Begin package load [ProjectSystemPackage]</description>
<guid>{8716B03B-8A63-4FAB-A1DB-81FB3918374A}</guid>
</entry>
<entry>
<record>769</record>
<time>2020/11/03 11:21:15.270</time>
<type>Error</type>
<source>VisualStudio</source>
<description>SetSite failed for package [ProjectSystemPackage]Source: 'Devsense.VisualStudio.ProjectSystem' Description: Could not load file or assembly 'Microsoft.VisualStudio.Threading, Version=16.6.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a' or one of its dependencies. The system cannot find the file specified.
System.IO.FileNotFoundException: Could not load file or assembly 'Microsoft.VisualStudio.Threading, Version=16.6.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a' or one of its dependencies. The system cannot find the file specified.
File name: 'Microsoft.VisualStudio.Threading, Version=16.6.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a'
 at Devsense.VisualStudio.ProjectSystem.ProjectSystemPackage.InitializeAsync(CancellationToken cancellationToken, IProgress`1 progress)
 at Microsoft.VisualStudio.Shell.AsyncPackage.<>c__DisplayClass20_0.<<Microsoft-VisualStudio-Shell-Interop-IAsyncLoadablePackageInitialize-Initialize>b__1>d.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
 at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
 at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
 at Microsoft.VisualStudio.Threading.JoinableTask.<JoinAsync>d__68.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
 at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
 at Microsoft.VisualStudio.Services.VsTask.RethrowException(AggregateException e)
 at Microsoft.VisualStudio.Services.VsTask.InternalGetResult(Boolean ignoreUIThreadCheck)
 at Microsoft.VisualStudio.Services.VsTask.GetResult()

WRN: Assembly binding logging is turned OFF.
To enable assembly bind failure logging, set the registry value [HKLM\Software\Microsoft\Fusion!EnableLog] (DWORD) to 1.
Note: There is some performance penalty associated with assembly bind failure logging.
To turn this feature off, remove the registry value [HKLM\Software\Microsoft\Fusion!EnableLog].
</description>
<guid>{8716B03B-8A63-4FAB-A1DB-81FB3918374A}</guid>
<hr>80070002</hr>
<errorinfo></errorinfo>
</entry>
<entry>
<record>770</record>
<time>2020/11/03 11:21:15.279</time>
<type>Error</type>
<source>VisualStudio</source>
<description>End package load [ProjectSystemPackage]</description>
<guid>{8716B03B-8A63-4FAB-A1DB-81FB3918374A}</guid>
<hr>80070002</hr>
<errorinfo></errorinfo>
</entry>
<entry>
<record>771</record>
<time>2020/11/03 11:21:15.811</time>
<type>Information</type>
<source>VisualStudio</source>
<description>Begin package load [PhpTestPackage]</description>
<guid>{36E83D64-0D9D-4A14-9A17-ABE323C6F91B}</guid>
</entry>
<entry>
<record>772</record>
<time>2020/11/03 11:21:15.821</time>
<type>Error</type>
<source>VisualStudio</source>
<description>SetSite failed for package [PhpTestPackage]Source: 'Devsense.VisualStudio.Shell' Description: Could not load type 'Microsoft.VisualStudio.Shell.ServiceProvider' from assembly 'Microsoft.VisualStudio.Shell.Framework, Version=16.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a'.
System.TypeLoadException: Could not load type 'Microsoft.VisualStudio.Shell.ServiceProvider' from assembly 'Microsoft.VisualStudio.Shell.Framework, Version=16.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a'.
 at Devsense.VisualStudio.Shell.Services.get_GlobalProvider()
 at Devsense.VisualStudio.Shell.Services.get_IFeedbackService()
 at PHP.VisualStudio.TestAdapter.PhpTestPackage.<InitializeAsync>d__14.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
 at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
 at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
 at Microsoft.VisualStudio.Shell.AsyncPackage.<>c__DisplayClass20_0.<<Microsoft-VisualStudio-Shell-Interop-IAsyncLoadablePackageInitialize-Initialize>b__1>d.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
 at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
 at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
 at Microsoft.VisualStudio.Threading.JoinableTask.<JoinAsync>d__68.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
 at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
 at Microsoft.VisualStudio.Services.VsTask.RethrowException(AggregateException e)
 at Microsoft.VisualStudio.Services.VsTask.InternalGetResult(Boolean ignoreUIThreadCheck)
 at Microsoft.VisualStudio.Services.VsTask.GetResult()</description>
<guid>{36E83D64-0D9D-4A14-9A17-ABE323C6F91B}</guid>
<hr>80131522</hr>
<errorinfo></errorinfo>
</entry>
<entry>
<record>773</record>
<time>2020/11/03 11:21:15.833</time>
<type>Error</type>
<source>VisualStudio</source>
<description>End package load [PhpTestPackage]</description>
<guid>{36E83D64-0D9D-4A14-9A17-ABE323C6F91B}</guid>
<hr>80131522</hr>
<errorinfo></errorinfo>
</entry>