Why TextEditor is in read-only?

Hi guys!

I have created a custom provider, and I can show the file's content inside the editor. However, for some reason, I can't change its content. It feels like the editor is in read-only mode.  Could you please give me any hints of what is going on?

import com.intellij.openapi.actionSystem.*;
import com.intellij.openapi.editor.EditorFactory;
import com.intellij.openapi.fileEditor.FileEditor;
import com.intellij.openapi.fileEditor.FileEditorLocation;
import com.intellij.openapi.fileEditor.FileEditorState;
import com.intellij.openapi.fileEditor.FileEditorStateLevel;
import com.intellij.openapi.fileEditor.impl.text.TextEditorProvider;
import com.intellij.openapi.project.Project;
import com.intellij.openapi.util.IconLoader;
import com.intellij.openapi.util.Key;
import com.intellij.openapi.vfs.VirtualFile;
import org.jetbrains.annotations.NotNull;
import org.jetbrains.annotations.Nullable;

import javax.swing.*;
import java.awt.*;
import java.beans.PropertyChangeListener;

public class CustomSqlFileEditor implements FileEditor {
    private final FileEditor myEditor;
    private final VirtualFile file;
    JPanel panel;

    CustomSqlFileEditor(Project project, VirtualFile file) {
        this.file = file;
        EditorFactory editorFactory = EditorFactory.getInstance();
        //Document document = editorFactory.createDocument(LoadTextUtil.loadText(file));
        //myEditor = editorFactory.createEditor(document, project, file, false);  // readOnly set to false

        myEditor = TextEditorProvider.getInstance().createEditor(project, file);
        panel = new JPanel(new BorderLayout());

    }

    @NotNull
    @Override
    public VirtualFile getFile() {
        return file;
    }


    @NotNull
    @Override
    public JComponent getComponent() {
        DefaultActionGroup actionGroup = new DefaultActionGroup();

        Icon icon = IconLoader.findIcon("./assets/icons/play.svg");
        actionGroup.add(new AnAction("Button 1", "Button 1 description", icon) {
            @Override
            public void actionPerformed(@NotNull AnActionEvent e) {
            }
        });
        ActionToolbar toolbar = ActionManager.getInstance().createActionToolbar(ActionPlaces.TOOLBAR, actionGroup, true);
        toolbar.setTargetComponent(myEditor.getComponent());  // set target component
        panel.add(toolbar.getComponent(), BorderLayout.NORTH);
        panel.add(myEditor.getComponent(), BorderLayout.CENTER);
        return panel;
    }

    @Override
    public JComponent getPreferredFocusedComponent() {
        //return myEditor.getContentComponent();
        return myEditor.getPreferredFocusedComponent();
    }

    @NotNull
    @Override
    public String getName() {
        return "Custom SQL File Editor";
    }

    @Override
    public void setState(@NotNull FileEditorState state) {
        // Do nothing
    }

    @Override
    public void dispose() {
       // EditorFactory.getInstance().releaseEditor(myEditor);
        TextEditorProvider.getInstance().disposeEditor(myEditor);
    }

    @Override
    public boolean isModified() {
        return false;
    }

    @Override
    public boolean isValid() {
        return true;
    }

    @Override
    public void selectNotify() {
    }

    @Override
    public void deselectNotify() {
    }

    @Override
    public void addPropertyChangeListener(@NotNull PropertyChangeListener listener) {
    }

    @Override
    public void removePropertyChangeListener(@NotNull PropertyChangeListener listener) {
    }

    @Override
    public @Nullable FileEditorLocation getCurrentLocation() {
        return null;
    }

    @NotNull
    @Override
    public FileEditorState getState(@NotNull FileEditorStateLevel level) {
        return new FileEditorState() {
            @Override
            public boolean canBeMergedWith(FileEditorState otherState, FileEditorStateLevel level) {
                return false;
            }
        };
    }

    @Override
    public <T> T getUserData(@NotNull Key<T> key) {
        return null;
    }

    @Override
    public <T> void putUserData(@NotNull Key<T> key, T value) {
    }
}