Angular 7: unwanted redirect when query parameters are present - router

Question

I use #angular/router with angular 7.
My goal is to use an arbitrary number of (optional) query parameters on one of my pages, in particular in /pages/components
The problem I face is that whenever I enter some query parameters in my URL bar, I get redirected to a weird location. This redirect happens for all my pages, if any query parameter is present.
Example:
http://localhost:4200/pages/dashboard (works fine)
http://localhost:4200/pages/components (works fine)
http://localhost:4200/pages/dashboard?hello=55&world=77 : not working. I get redirected to http://localhost:4200/pages/components/lo%3D55&world%3D77
I am struggling to make sense out of this redirection.
It looks like the first query parameter has its first 3 letters cut off, the rest of the query string is escaped, and for some reason I always end up in /pages/components/something, even if the url that I typed was a totally different page (maybe because components-page is my only page with a parameter on the RouterModule?).
Here is my routing module:
const appRoutes: Routes = [
{path: '', component: LoginPageComponent, runGuardsAndResolvers:'always', pathMatch: 'full'},
{path: 'pages/components', component: ComponentsPageComponent, runGuardsAndResolvers: 'always'},
{path: 'pages/classes', component: ClassesPageComponent, runGuardsAndResolvers: 'always'},
{path: 'pages/components/:id', component: ComponentsPageComponent, runGuardsAndResolvers: 'always'},
{path: 'pages/dashboard', component: DashboardPageComponent, runGuardsAndResolvers: 'always'},
{path: 'pages/users', component: UserAdminisitrationComponent, runGuardsAndResolvers: 'always', canActivate: [UserRoleGuardService]},
{path: 'pages/reports', component: ReportsPageComponent, runGuardsAndResolvers: 'always'},
{path: 'pages/jobs', component: JobsPageComponent, runGuardsAndResolvers: 'always'},
{path: 'pages/material', component: MaterialPageComponent, runGuardsAndResolvers: 'always', canActivate: [UserRoleGuardService]},
{path: '**', redirectTo: '/pages/dashboard', pathMatch: 'full'}
];
#NgModule({
imports: [RouterModule.forRoot(appRoutes)],
exports: [RouterModule]
})
export class AppRoutingModule {
}

Answer 1

I had the same problem with Angular 8,
i was doing that :
this.returnUrl = this.route.snapshot.queryParams['returnUrl']
....
this.router.navigate([this.returnUrl]);
when this.returnUrl = "/my-componenet?x=4"; for example i was redirected to "/my-componenet%3Fx%3D4" instead.
the fix was to use navigateByUrl instead
i also added a decodeURI (just in case)
this.returnUrl =decodeURI(this.route.snapshot.queryParams['returnUrl'] || '/login')
....
this.router.navigateByUrl(this.returnUrl);