fixup! rework Known limitations in doc + add GH issues

Signed-off-by: Miroslav Bajtoš <[email protected]>

docs/site/Importing-LB3-models.md

@@ -37,46 +37,77 @@ support applications that are unable to boot (throw errors at startup).
 
 ## Known limitations
 
-- Connector-specific metadata in property definitions is not imported.
+{% include note.html content="
+Please up-vote the tracking GitHub issue for scenarios that are important to
+your project. It will help us to better prioritize which limitations to remove
+first.
+" %}
+
+### Connector-specific metadata in property definitions is not imported
+
+_The tracking GitHub issue:
+[loopback-next#3810](https://github.com/strongloop/loopback-next/issues/3810)_
+
+Workaround: Add this metadata manually to the generated file.
+
+### Nested properties are not upgraded
+
+_The tracking GitHub issue:
+[loopback-next#3811](https://github.com/strongloop/loopback-next/issues/3811)_
+
+When a property is defined with a complex object type, the nested property
+definitions are not converted from LB3 to LB4 format.
+
+Workaround: Fix the generated definition manually.
+
+### Model relations are not imported
+
+_The tracking GitHub issue:
+[loopback-next#3812](https://github.com/strongloop/loopback-next/issues/3812)_
+
+Workaround: define relational metadata & navigational properties manually.
+
+### Models inheriting from custom base class
+
+_The tracking GitHub issue:
+[loopback-next#3813](https://github.com/strongloop/loopback-next/issues/3813)_
 
-  As a workaround, you can add this metadata manually to the generated file.
+Models inheriting from application-specific models (including LB3 built-in
+models like `User`) cannot be imported yet.
 
-- When a property is defined with a complex object type, the nested property
-  definitions are not converted from LB3 to LB4 format.
+Workaround:
 
-  As a workaround, you can fix the generated definition manually.
+1. Modify your LB3 model to inherit from `Model`, `PersistedModel` or
+   `KeyValueModel`.
 
-- Model relations are not imported.
+2. Import the model to LB4
 
-  As a workaround, you can define relational metadata & navigational properties
-  manually.
+3. Update the imported model to inherit for the desired application-specific
+   model.
 
-- Models inheriting from application-specific models (including LB3 built-in
-  models like `User`) cannot be imported yet.
+### MongoDB's `ObjectID` type
 
-  As a workaround, you can modify your LB3 model to inherit from `Model`,
-  `PersistedModel` or `KeyValueModel`, then import the model and finally update
-  the generated model file to inherit for the desired application-specific
-  model.
+The tracking GitHub issue:
+[loopback-next#3814](https://github.com/strongloop/loopback-next/issues/3814).
 
-- For models attached to MongoDB datasource, the imported LB4 model contains
-  incorrect definition of the primary key property of `ObjectID` type.
+For models attached to MongoDB datasource, the imported LB4 model contains
+incorrect definition of the primary key property of `ObjectID` type.
 
-  As a workaround, you can change the property definition from:
+As a workaround, you can change the property definition from:
 
-  ```ts
-  @property({
-    type: ObjectID;
-  })
-  id: ObjectID;
-  ```
+```ts
+@property({
+  type: ObjectID;
+})
+id: ObjectID;
+```
 
-  to:
+to:
 
-  ```ts
-  @property({
-    type: 'string',
-    mongodb: {dataType: 'ObjectID'}
-  })
-  id: string;
-  ```
+```ts
+@property({
+  type: 'string',
+  mongodb: {dataType: 'ObjectID'}
+})
+id: string;
+```